; Pre-season On 19 December 2018
Rodolfo Landim was sworn in as Flamengo's new president after being elected on the 8th and officially took over official administrative roles on 1 January. Eduardo Bandeira de Mello had been president for two 3-year terms. Before officially taking office, Landim announced that plans to hire
Abel Braga as the new head coach in 2019 were already underway. Braga was officially announced as the replacement to
Dorival Júnior at the start of the new year. Braga had previously managed Flamengo in 2004. On 29 December a deal for
São Paulo center-back
Rodrigo Caio was reportedly closed on 29 December — €5m for five years and 45% of the player's rights. On 8 January Flamengo reached an agreement with
Cruzeiro to sign highly-sought attacking midfielder
de Arrascaeta for
R$55.3m in three installments, the largest transfer fee in Flamengo's history. The Uruguayan player was officially announced on 12 January. On 8 January it was reported that Flamengo had secured a loan deal for striker
Gabriel Barbosa, the leading goalscorer in the
2018 Brasileirão and the
Copa do Brasil while on loan with
Santos. The club negotiated the loan with
Inter Milan, Gabriel's contract holders. Flamengo paid no loan fee but are responsible for the entirety of his
R$15m /
€3.5m annual salary, the most expensive on the roster. In January Flamengo traveled to
Orlando, Florida for participation in the
2019 Florida Cup with friendly matches against
Ajax and
Eintracht Frankfurt. Rodrigo Caio was the only new signing to travel with the club for Flamengo's first trip to the United States in nearly 13 years. On 10 January Flamengo defeated Ajax on penalty kicks in the Florida Cup.
Fernando Uribe scored both goals for Flamengo in regular time, and
Veltman and
Magallán of Ajax missed their penalties. On 12 January Flamengo defeated Eintracht Frankfurt in Orlando City Stadium 1–0, goal scored by
Jean Lucas. The victory gave Flamengo the Florida Cup title on points (2 for the penalty win, 3 for the win). On 22 January, amidst rumors of a transfer to
Orlando City of
MLS, 33 year-old midfielder
Diego extended his contract with Flamengo until the end of 2020. His contract was set to expire in July and the club only agreed to renew with a reduction in salary. On 23 January, Flamengo and
Santos completed negotiations for the 28 year-old forward
Bruno Henrique to sign with Flamengo in exchange for R$23m paid in three installations, and a one-year loan of 22 year-old midfielder
Ronaldo to Santos for
€3m (R$12.9m). However disagreements over salary between Santos and Ronaldo caused the loan to fall through, and it was announced later in the month that Ronaldo would remain at Flamengo. A deal was later reached to loan 20 year-old
Jean Lucas to the São Paulo club instead. ;January On 20 January Flamengo began their 2019 campaign in the
Campeonato Carioca against
Bangu. In front of a crowd of 40 thousand in the
Maracanã, Flamengo conceded to the visitors within 3 minutes. Diego equalized on a 1st half penalty in an irregular play after the ball had gone out of bounds, and
Rhodolfo scored a header to seal the victory. Gabriel and Arrascaeta were presented to the fans but did not feature in the match. On 23 January Flamengo's reserve squad faced
Resende. Flamengo again conceded first before equalizing with a bicycle kick from
Henrique Dourado. On 26 January, Bruno Henrique scored both goals in his Flamengo debut: a 2–1 victory over
Botafogo, Flamengo's first
classico of the season. Flamengo's opponents again scored the first goal. ;February On 8 February, a fire at
Ninho do Urubu training center claimed the lives of 10 youth academy players. On 14 February Flamengo fell to rivals
Fluminense in the semi-final of the Taça Guanabara, their first match after the fire at the training center. On 25 February, Henrique Dourado traveled to China to join
Henan Jianye. Flamengo had negotiated a transfer of the striker for close to
€6m (of which Flamengo received 75%). On 26 February the club released their 30-man roster for the
Copa Libertadores group stage. ;March On 5 March, Flamengo's 1–0 victory against
San José in
Oruro, Bolivia in the Copa Libertadores marked the first time in history the club had won away from home in their first match of continental competition. On 13 March, Flamengo defeated
LDU in the Copa Libertadores 3–1.
Éverton Ribeiro scored early in the 1st half.
Diego committed a foul in the box against
Vega but
Diego Alves saved the penalty of
Intriago. Gabriel and Uribe scored in the 2nd half but
Borja scored once for LDU in the final moments. On 19 March Flamengo guaranteed their berth in the Carioca championship phase after defeating
Madureira 2–0 in the penultimate round of the Taça Rio. On 22 March Flamengo announced the closing of a deal with new primary kit sponsor Bank BS2. The deal is in place for 2 years and is valued at approximately
R$25m total. Adidas officially unveiled the 2019-20 Flamengo home kit on 22 March, and the team debuted it against Fluminense. On 24 March, Flamengo faced rivals Fluminense and won 3–2.
Miguel Trauco,
Robert Piris Da Motta, Giorgian de Arrascaeta, and
Gustavo Cuéllar were called up by their national teams to participate in friendlies before the
Copa América and were not available for the match. On 27 March Flamengo again faced Fluminense in the semifinal of the second phase of the Campeonato Carioca, the Taça Rio. Flamengo required a win, as Fluminense would advance with a draw. Éverton Ribeiro converted a penalty in stoppage time to win, 2–1. Prior to this, manager Abel Braga left the stadium citing throat pain and was treated at a hospital for
heart arrhythmia, before being discharged later. On 31 March Flamengo went on to defeat
Vasco on penalties to claim the club's 8th Taça Rio title. Since Flamengo had already qualified for the Carioca final stage, starters Diego and Gabriel Barbosa rested for both Taça Rio matches in preparation for the Copa Libertadores. ;April On 3 April, in Flamengo's highest-attended home match of the season, the team lost 0–1 to
Peñarol in the Copa Libertadores on a late goal by
Lucas Viatri. The match represented Peñarol's first victory as a visiting side in their previous sixteen Libertadores matches, dating back to
2013.
Gabriel was sent off via a straight red card after a reckless tackle against
Rodrigo Rojo. The result dropped Flamengo to second in the group, behind Peñarol on goal differential. On 6 April, Flamengo qualified for a final against Vasco after Gabriel equalized against Fluminense in the semi-final of the Campeonato Carioca (as the team with the greater overall point total across both phases of the Carioca, Flamengo advanced with a draw). The day prior to this match, it was confirmed by the governor of Rio de Janeiro that Flamengo and Fluminense would be joint-managers of the Maracanã for six months beginning on 19 April, a deal which allowed the clubs to pay a fixed monthly fee and receive a higher share of matchday revenue than was granted under the previous deal. Because Vasco da Gama was not included in the deal, the president of the club announced that the team would not play their home matches at the Maracanã. This included the first leg of the Carioca final against Flamengo, which was moved to
São Januário. On 11 April, Flamengo hosted San José in the Copa Libertadores and won emphatically by a score of 6–1 with Gabriel serving his red card suspension. The result returned Flamengo to the top of the group, ahead of Peñarol on goal differential. On 14 and 21 April, Flamengo won both legs of the Caroica final against Vasco by the scoreline 2–0, capturing their record 35th Carioca title.
Bruno Henrique scored both goals in the first leg and was the top goalscorer of the Campeonato Carioca. On 24 April in
Quito, Ecuador against LDU, Bruno Henrique scored early before Flamengo conceded a goal in the final seconds of the first half. A draw would have guaranteed Flamengo's qualification to the round of 16 and LDU's elimination.
Andrés Chicaiza of LDU scored an excellent goal in the second half to save his team from elimination. The result forced Flamengo to earn at least a draw against Peñarol in
Montevideo on the final matchday to guarantee passage. Abel Braga was not present for the match, as
CONMEBOL had suspended him for bringing his team out of the dressing room late after halftime against Peñarol. On 27 April the
2019 Campeonato Brasileiro season began. Flamengo played host to Cruzeiro. Bruno Henrique scored twice and Gabriel scored on a rebound to put the match at 3–1. Legendary Flamengo and
Seleção centre-back Juan entered the field for the final time in the closing minutes to mark his retirement from football. In the final play of the match, centre-back Rodrigo Caio suffered a head injury after colliding with
Dedé and exited the field in an ambulance. His was discharged from the hospital the following morning but would miss the following league match against
Internacional. ;May On 1 May, Flamengo fell to Internacional in
Porto Alegre 2–1, conceding the opening goal to former player
Paulo Guerrero. On 2 May, the team was drawn against
Corinthians in the Copa do Brasil round of 16, a rematch of the
previous edition's semi-final. On 5 May, in preparation for their crucial last Libertadores group stage match, Flamengo fielded a reserve team against São Paulo in the Brazilian championship and came away with a draw, goal scored by
Orlando Berrío. On 8 May, a victory or draw against
Peñarol in
Montevideo would guarantee qualification to the knockout stage of the tournament. In the final minutes of the match, substitute
Vitinho failed to score on a one-on-one opportunity, but the draw was sufficient to qualify.
Pará received two yellow cards in the match and was sent off. LDU's 4–0 victory over San José qualified them and eliminated Peñarol. Flamengo finished top of Group D with 10 points, tied with LDU and Peñarol but ahead on goal differential. On 12 May, Flamengo fielded their reserve team against
Chapecoense in the Maracanã in preparation for their mid-week Copa do Brasil match against Corinthians. Flamengo won 2–1 with goals from Vitinho and
Lincoln. On 13 May, Flamengo was drawn against Ecuadorian club
Emelec in the Libertadores round of 16. On 15 May against Corinthians in the
Arena Corinthians, Flamengo maintained high possession and won 1–0, with the goal scored by
Willian Arão on a cross from Bruno Henrique. On 18 May Flamengo debuted their 2019 white alternative kits against
Atlético Mineiro at the
Independencia. They lost 2–1 off a goal from
Yimmi Chará despite having a man advantage for the entire second half after the sending off of
Elias. Shortly thereafter, Flamengo's Gavea headquarters was vandalized with graffiti calling for the firing of Abel Braga. President Landim remarked that the graffiti was politically motivated and did not represent the views of most supporters. On 26 May in a dramatic match against the mixed reserve team of
Athletico Paranaense in the Maracanã, Flamengo were trailing 1–2 in the 90th minute. Bruno Henrique and
Rodrigo Caio each scored in stoppage time to win 3–2, preserving their home win streak in three league matches. On 29 May, Abel Braga officially resigned as manager of Flamengo citing external pressure from fans and lack of support from the board. Braga served as manager for five months with a record of 18 wins, 7 draws and 5 losses. Under his management, Flamengo scored 56 and conceded 27 goals in 30 official matches. On 29 May, it was confirmed that striker Fernando Uribe would transfer to Santos. Since July 2018, he scored 8 goals in 37 appearances for Flamengo. ;June , signed on 1 June 2019. On 1 June, Flamengo confirmed the signing of
Portuguese manager
Jorge Jesus. Under interim manager Marcelo Salles, Flamengo won three matches and drew once, against Fluminense. On 4 June, the club defeated Corinthians in the Maracanã 1–0 to advance to the quarter-finals of the Copa do Brasil. In the Brazilian championship, Flamengo defeated
Fortaleza and
CSA. Jorge Jesus was a spectator for the match against Fluminense and assumed his managerial role on 20 June. Three Flamengo players joined their national teams for the Copa América: Gustavo Cuéllar of Colombia, Giorgian de Arrascaeta of Uruguay, and Miguel Trauco of Peru. Cuéllar scored a goal against Paraguay. Trauco's Peru advanced to the final against Brazil, and Trauco was named to the Team of the Tournament by CONMEBOL. On 9 June, Flamengo confirmed the signing of Brazilian right-back
Rafinha as a free agent after his eight-year career at
Bayern Munich. and contacted Miguel Trauco to request the use of his shirt number 13, the same number Rafinha wore for Bayern. On 20 June, Flamengo came to an agreement with French club Lyon for the transfer of midfielder Jean Lucas, on loan with Santos. Flamengo received €6.35m of the €8m transfer. On 29 June Flamengo played a training match against Madureira. It served as the first match managed by
Jorge Jesus. ;July On 9 July, promising midfielder
Ronaldo was loaned to
Bahia for the remainder of the year. On 10 July in the Brazilian managerial debut of Jorge Jesus, Flamengo tied 1–1 against
Athletico Paranaense in the
Arena da Baixada for the Copa do Brasil quarter-finals, with the equalizing goal scored by Gabriel. The match was marked by several uses of
VAR. On 11 July Flamengo announced the signing of Spanish central defender
Pablo Marí, previously on loan with
Deportivo La Coruña from
Manchester City. He signed with Flamengo through December 2022. On 12 July, Flamengo closed a deal with
Roma for Brazilian midfielder
Gerson. The former Fluminense player was transferred for €11.8m in exchange for 100% of the player's economic rights, making him the most expensive Brazilian player ever signed by a Brazilian club. Gerson signed a contract through 2023. On 14 July in Flamengo's return to the Brasileirão they defeated
Goiás 6–1 in a sold-out Maracanã with a
hat-trick from Arrascaeta. Rafinha made his Flamengo debut. On 17 July Flamengo faced Athletico Paranaense in the return leg of the Copa do Brasil quarter-final. Gabriel scored in the 2nd half but
Rony of Athletico responded. Tied 1–1, the match was decided by penalties. Diego took the first penalty and his shot was saved. Athletico Paranaense went on to win the shootout 3–1 and eliminate Flamengo from the competition. On 19 July Flamengo released their 30-man roster for the Copa Libertadores round of 16. New signings Rafinha, Pablo Marí, João Lucas, and Gerson, along with
Lincoln, were the additions. On 21 July Flamengo played to a 1–1 draw against Corinthians.
Clayson converted a penalty after Berrío fouled
Vágner Love, and Gabriel scored a goal initially ruled
offside but reversed by VAR. On 23 July, Flamengo announced the signing of
Filipe Luís after his farewell from eight seasons at
Atlético Madrid. Because the signing was made after 9 July, he was not eligible to participate in the Copa do Brasil. On 24 July the team faced Emelec in
Guayaquil and suffered a 2–0 loss in the opening leg of the Libertadores round of 16. With Éverton Ribeiro, de Arrascaeta and Vitinho injured, Jorge Jesus started Rafinha as a winger, with
Diego in front of Gerson and Arão in the midfield.
Rodinei occupied the right-back spot. Emelec scored an early goal and led at halftime. Early in the second half,
Vega of Emelec received a straight red card for a high-kick to the face of Rafinha. Flamengo made three substitutions shortly after, bringing on
Lincoln and
Lucas Silva for the attack. Twenty minutes after the red card, Diego left the field with a serious ankle fracture that would require surgery. Both teams playing with 10 men, Emelec scored again late in the match. On 28 July, Flamengo faced rivals Botafogo in the 12th round of the league and won 3–2 after conceding the first goal. Gabriel scored in his fifth consecutive league match. Rodrigo Caio and
Lincoln both exited the match with injuries. After the match, Jorge Jesus confirmed that the transfer of
Léo Duarte to
Milan had been completed. The centre-back left Flamengo for €10 million. The club had 75% of his economic rights. On 30 July Flamengo released the contract of right-back Pará, leaving him free to sign with Santos. On 31 July Flamengo hosted Emelec in the return leg of the Copa Libertadores round of 16. Trailing 0–2 on aggregate,
Gabriel converted a penalty after Rafinha is fouled by
Bagüi, and later scores from close range after recovering a pass from Bruno Henrique.
Reinier makes his senior team debut in the 2nd half. In the penalty shootout, all four Flamengo players score. Diego Alves saved Dixon Arroyo's shot and
Nicolás Queiróz hit the crossbar. ;August On 1 August, left-back Miguel Trauco's departure to French club
Saint-Étienne for R$2.5m (approximately €600k) was confirmed. His contract was set to expire at the end of the season. On 4 August, Flamengo fell to Bahia 0–3 on a hat-trick from
Gilberto. Filipe Luís made his Flamengo debut. Flamengo debuted their 2019-2020 alternative kits in the match: dark grey with lime green details. On 10 August Flamengo defeated
Grêmio 3–1 in the Maracanã. de Arrascaeta recorded a goal and an assist. Grêmio played a team of mostly reserves in preparation for their mid-week Copa do Brasil semi-final. On 15 August, Flamengo announced that they had ceased negotiations with Italian striker
Mario Balotelli. On 16 August, Bruno Henrique was called up to the
Brazil National Team for the first time for a pair of friendlies in September. Arrascaeta was called up to the
Uruguay National Team for the same window. The club also unveiled their list of players registered for the Copa Libertadores quarter-finals. With three players transferred out (Pará, Trauco and Léo Duarte), Filipe Luís and Matheus Dantas were added to the roster. On 17 August, Flamengo defeated Vasco da Gama 4–1 in Brasilia in the highest attended match of the Brasileirao season so far. The victory moved Flamengo into 2nd place. On 21 August, Flamengo faced Internacional in the home leg of the Copa Libertadores quarter-finals. Bruno Henrique scored twice in the seconds half, minutes apart, to secure a 2–0 victory. On 23 August the club released an official statement that Gustavo Cuéllar would be suspended from club activities indefinitely for refusing to travel with the team for the following league match, citing family matters. It was reported that Cuéllar had been seeking to exit Flamengo on an offer from
Al-Hilal. On 25 August, Flamengo defeated
Ceará 3–0 in
Fortaleza to assume leadership of the Brazilian Championship. de Arrascaeta scored a bicycle kick goal in stoppage time, assisted by Rafinha. On 26 August, an official announcement from the club declared that Cuéllar would be re-integrated into the team and would travel for the second leg of the Copa Libertadores quarter-final against Internacional. On 27 August, Orlando Berrío was called to the Colombia national team for September friendlies. On 28 August, Flamengo qualified for the Copa Libertadores semi-final after drawing against Internacional.
Rodrigo Lindoso scored a header from a set-piece, and Gabriel equalized on a counter-attack assisted by Bruno Henrique. Flamengo advanced with a 3–1 aggregate score to their first Copa Libertadores semi-final since 1984. On 30 August, Gustavo Cuéllar was officially announced as a new signing by
Al-Hilal. Flamengo reopened negotiations with the club and the player was signed for a reported fee of
€7.5m. Cuéllar made 170 appearances for Flamengo since 2016. It was Flamengo's first victory against Palmeiras since May 2014. Manager
Luiz Felipe Scolari was dismissed by Palmeiras following the loss. On 7 September, Flamengo defeated
Avaí 3–0 in the
Mané Garrincha Stadium in
Brasília. Reinier scored his first goal for the senior team. On 14 September Flamengo hosted Santos for their final match of the first half of the Brasileirão. Gabriel scored the only goal of the match, a chip shot from outside the penalty area. Flamengo maintained their lead in the league and Santos fell to third place. On 20 September, Tite called up Gabriel and Rodrigo Caio for a pair of national team friendlies against
Senegal and
Nigeria in October. Giorgian de Arrascaeta and Orlando Berrío were also called to their national teams for the same window, all four becoming unavailable against Atlético Mineiro and Athletico Paranaense. As a result, Flamengo requested that Reinier not be called up for the
2019 FIFA U-17 World Cup to be played in Brazil during that same period. On 21 September the club faced Cruzeiro in Belo Horizonte. Giorgian de Arrascaeta scored against his former club, and Gabriel scored to win 1–2. The win set a club record of seven straight victories in the national league (Flamengo had previously won six straight in 1978, 1982, and 2015). On 25 September Flamengo hosted Internacional at the Maracanã. Inter had two key players sent off with red cards early:
Bruno Vieira in the 18th minute for a foul against Gabriel, and former Flamengo player Paolo Guerrero for complaining after a collision with Rodrigo Caio at the end of the first half. Gabriel converted his penalty, and de Arrascaeta and Bruno Henrique also scored to win 3–1. The result extended the club's record winning streak to eight matches. On 28 September Flamengo faced São Paulo at home in
Fernando Diniz's managerial debut. Starters Gerson, Rafinha and Filipe Luís entered in the 2nd half, but the match ended in a scoreless draw. This was Flamengo's first failure to win at the Maracanã in 2019 league play. Flamengo moved to four points clear of Palmeiras in first place.
October On 2 October, Flamengo faced Grêmio in
Porto Alegre for the first leg of the Copa Libertadores semi-final. Flamengo had three goals annulled by VAR and finished tired 1–1 with a goal from Bruno Henrique. On 6 October, Flamengo faced last-place Chapecoense away. With Gabriel suspended and Arrascaeta and Filipe Luís injured, the team managed to win 1–0 via a goal from Bruno Henrique. On 10 October, Flamengo defeated Atlético Mineiro 3–1 at the Maracanã with a goal and two assists from Vitinho to open up an eight-point lead in the league. On 13 October, the team traveled to the
Arena da Baixada to face Athletico Paranaense. An early penalty decision in favor of Athletico was withdrawn after VAR review, and Bruno Henrique scored another brace to secure a 2–0 victory, breaking a 45-year spell of Flamengo's failure to win against Athletico Paranaense as a visitor. On 16 October, Flamengo came from behind to defeat
Fortaleza 2–1 at the
Castelão with a goal by Reinier. Fortaleza challenged the result on account of a second ball entering the field during the match-winning goal, but the appeal was denied. On 23 October in the second leg of the Copa Libertadores semi-final at the Maracanã, Flamengo advanced against Grêmio with an astonishing 5–0 victory. The result matched the largest ever margin of victory in the Libertadores between two Brazilian clubs. Flamengo advanced 6–1 on aggregate to their first Copa Libertadores final since their championship in 1981. On 25 October, the selection for the Brazil national team's November friendlies against
Argentina and
South Korea were made. Flamengo reportedly requested that none of their players be called up, and none were. Manager Tite expressed interest in
Gerson. On 27 October the team defeated
CSA 1–0. The match attendance at the Maracanã set the 2019 Brasileirão record with paid attendance of 65,649. On 31 October, Flamengo drew 2–2 against Goiás. Gabriel scored a goal and received a yellow card in the match, becoming disqualified from the following league match against Corinthians.
November On 3 November, Bruno Henrique scored a hat-trick as part of a 4–1 home rout against Corinthians. Diego Alves returned from injury and was available for the match. On 5 November in reaction to the ongoing
civil protests in Chile, CONMEBOL, Flamengo and
River Plate agreed to relocate the Copa Libertadores final from
Santiago to
Lima, Peru. On 7 November, with de Arrascaeta injured Flamengo defeated Botafogo 0–1 in a challenging match with a late game-winner from
Lincoln. On 9 November, Reinier extended his contract with Flamengo through 2024 with a reduction in his release clause from €70 to €35 million. On 10 November, Flamengo defeated Bahia 3–1 at the Maracanã. On 13 November, Flamengo played to a difficult 4–4 draw against rivals Vasco da Gama. Éverton Ribeiro scored in the first 40 seconds, and
Marrony equalized in the 34th minute. Trailing 2–3, Bruno Henrique scored a brace to take the lead before
Ribamar equalized in stoppage time. This was Bruno Henrique's fourth brace in the 2019 Brasileirão in addition to three braces in the Campeonato Carioca. On 17 November Flamengo defeated Grêmio 0–1 in the Campeonato Brasileiro, breaking the club's 21st Century undefeated streak record of 25 matches (set in 2011). Gabriel scored the lone goal of the match and received a red card, becoming the most booked player of the 2019 Série A season. The victory also set the Campeonato Brasileiro Série A record for most wins in 38-match round-robin season with 25, breaking the previous record of 24 wins held by 2014 Cruzeiro, 2015 Corinthians, and 2016 Palmeiras. On 20 November, the team embarked to Lima for the Copa Libertadores final and released their list of available players. On 23 November, Flamengo entered the
Estadio Monumental in Lima for their historic single-match Copa Libertadores final against defending champions
River Plate. Managed by
Marcelo Gallardo, River controlled play for much of the first half. In the 14th minute,
Rafael Santos Borré of River Plate scored after Willian Arão and Gerson failed to clear a ball in the penalty area. Flamengo trailed 0–1 at halftime. In the second half, Flamengo's play improved as Gabriel continued to be well-marked by River's defense. In the 57th minute Flamengo shockingly failed to equalize, as Éverton Ribeiro shot from inside the penalty area but was denied by goalkeeper
Franco Armani. In the 65th minute, captain Diego was substituted on for Gerson in the midfield. Vitinho entered for Arão in the 85th minute. Still trailing by one goal, Diego and de Arrascaeta pressured
Lucas Pratto to force a turnover. de Arrascaeta found Bruno Henrique who advanced into the attacking half before returning a through-ball to de Arrascaeta in the penalty area where he provided the assist to Gabriel's equalizing goal in the 89th minute. Minutes later, Diego lifted a deep forward pass into the area towards Gabriel. River Plate centre-back
Javier Pinola failed to clear the ball and Gabriel scored with his first touch to complete the historic comeback. After trailing for much of the match, Flamengo won their second Copa Libertadores. Gabriel Barbosa was named Man of the Match and finished as the top goalscorer of the Copa Libertadores with nine goals. Bruno Henrique was named best player of the tournament. The victory qualified Flamengo to their first
FIFA Club World Cup in December in Qatar, as well as the
2020 Recopa Sudamericana against
Copa Sudamericana champions
Independiente del Valle. The result also likely qualified Flamengo to the expanded
FIFA Club World Cup, which was to be played in China. On 24 November, fewer than 24 hours after the finish in the Copa Libertadores, Flamengo clinched their sixth Campeonato Brasileiro championship as a result of Grêmio's 1–2 victory over Palmeiras. With four league matches still to play, Flamengo became the first Brazilian team since
Pelé's 1962 and 1963 Santos teams to win the Copa Libertadores and Campeonato Brasileiro in the same season. With the championship, Flamengo qualified for the
2020 Supercopa do Brasil against Copa do Brasil champions
Athletico Paranaense. On 27 November with the league title already won, Flamengo took the field at the Maracanã against
Ceará. Bruno Henrique scored his second hat-trick of the season en route to a 4–1 victory. The team received the Série A trophy on the field after the match. The victory set a new points record in the era of the league's current format (2006–present) with 84, surpassing Corinthians' 2015 total of 81.
December On 1 December, Flamengo traveled to the
Allianz Parque to face Palmeiras for the 36th round of the Brazilian league. Amidst public safety concerns and fear of clashes between supporters groups, CBF upheld the request from São Paulo police that visiting supporters not be permitted in the stadium, a decision which Flamengo opposed. Flamengo opened the scoring early with a goal from Arrascaeta and two from Gabriel, defeating Palmeiras 1–3. This was Flamengo's first victory at the Allianz Parque since its completion in 2014. The victory set another league record in the post-2006 era: 80 goals scored in the campaign surpassed Cruzeiro's mark of 77 from 2013. Additionally, Gabriel Barbosa broke the league goal-scoring record in the 20-team era with his 24th goal of the season, passing
Jonas from 2010 Grêmio and
Borges from 2011 Santos. On 4 December Flamengo released their list of players for the Club World Cup. On 5 December in their final home match of the season, Flamengo defeated already relegated
Avaí by a score of 6–1 with a mostly reserve lineup. Gabriel scored his 25th goal of the season and 17 year-old Reinier scored a second-half brace. Flamengo finished league play undefeated at home. On 8 December on the final matchday of the season, Flamengo suffered their worst loss of the year falling 4–0 to league runners-up
Santos at the
Vila Belmiro. With the defeat, Flamengo equaled the record for fewest losses in a 38-match season with four, a mark set by São Paulo in 2006 and Palmeiras in 2018. On 9 December, several Flamengo players were honored at the 2019
Bola de Prata and
Prêmio Craque do Brasileirão awards. Gabriel received the Bola de Ouro for best player of the season, and Bruno Henrique received the "Craque do Brasileirão" award for player of the year. Jorge Jesus was honored as the best manager of the year by both awarding bodies. On 17 December Flamengo made their Club World Cup debut against
AFC Champions League winners
Al Hilal of Saudi Arabia in Doha, Qatar. After conceding the first goal to
Salem Al-Dawsari, Flamengo shone in the second half with a goal and assist from Bruno Henrique, and a late own goal against Al-Hilal to win 3–1 and secure a place in the final. On 18 December
Liverpool defeated
Monterrey in the opposite semi-final to confirm a rematch of the
1981 Intercontinental Cup against Flamengo. On 21 December, Flamengo and Liverpool entered the
Khalifa International Stadium for the FIFA Club World Cup final and Flamengo's final match of the 2019 season. Forward
Roberto Firmino of Liverpool nearly scored in the first minute of play. After resisting early chances, Flamengo matched Liverpool's play with chances from Bruno Henrique and maintained nearly 60% possession in the 1st half. In the 2nd half Firmino again came close, with a shot off the post. Éverton Ribeiro and de Arrascaeta came off for Diego and Vitinho. In 2nd half stoppage time, Liverpool was awarded a penalty after Rafinha fouled
Sadio Mané on the edge of the penalty area, but the decision was reversed by VAR and the match went into extra time tied 0–0. Liverpool continued to pressure and finally scored in the 9th minute: Mané found Firmino in the box who scored the match's only goal. Flamengo was unable to respond, coming close with an opportunity from substitute
Lincoln in the second period of extra time. Liverpool won 1–0, claiming their first Club World Cup with Firmino being named Man of the Match. Bruno Henrique received the Silver Ball of the tournament behind
Mohamed Salah of Liverpool's Golden Ball. On 31 December Gabriel was elected "Rey del Fútbol de América" ("South American Footballer of the Year") by Uruguayan paper
El País. Teammates Bruno Henrique and de Arrascaeta finished second and third in voting. ==Pre-season and friendlies==