Early career The roots of Castaignos' family are located in the département of
Landes, one hundred kilometers south of
Bordeaux in the south-west of France. There, Castaignos' father, the French-born Jean-Luc Castaignos, met Castaignos' mother who is of
Cape Verdean descent and holder of an Italian passport. In October 1990, two years before Luc's birth, the family moved to the Netherlands. The youngster lived close to Sportpark Thurlede, the home ground of the Catholic club. His former Excelsior '20 coach, Paul Benschop, was soon convinced by Castaignos' quality: "Everyone could see how much potential he had. Whenever we conceded a goal, Luc would take care of business." At the age of 13, he participated on regional club Spartaan '20's opening day. The club from Rotterdam, youth partner of Feyenoord, saw plenty of potential in the youngster and invited him to join. Castaignos only played one season for Spartaan '20. When various professional clubs showed their interest, Spartaan '20 warned Feyenoord. He then progressed through the
academy.
Feyenoord in 2011 After a successful performance with the Netherlands U17 at the
2009 UEFA European Under-17 Football Championship, a clutch of sides were linked to the Dutch youngster. Besides
Arsenal, also
Liverpool,
Manchester United,
Real Madrid,
Inter Milan,
Bayern Munich and
TSG 1899 Hoffenheim showed their interest in the Feyenoord's top scorer. However, on 22 July 2009, Castaignos crushed all rumours and told Feyenoord manager
Mario Been and technical advisor
Leo Beenhakker that he wanted to stay in Rotterdam. On 21 June 2009, Been announced he invited Castaignos to train with the first team squad a few times a week. On 13 August 2009, he trained with the first team squad for the first time. Castaignos made his official debut in Feyenoord's first team on 24 September 2009 replacing
Leroy Fer in the 72nd minute in the
KNVB Cup away match against
Harkemase Boys and helped the club win 5–0. After making his first team debut for Feyenoord, he said: "It's strange, because I haven't really proven anything yet. My strengths are my speed and scoring ability, the heading and my left leg could be even better. I can learn a lot from a player like
Roy Makaay. Now and then I ask for advice, but I mainly look at the training at which moments he walks away and so on. My debut is a first step, but there are still many steps to follow." At one point, due to his lack of first team opportunities, Castaignos was expected to be loaned out to
SBV Excelsior but he ended up staying at the club due to his latter injury. Five months later after making his first team debut and being on the unused bench, Castaignos made his debut, coming on for
Jon Dahl Tomasson in a 3–2 loss against
Groningen on 28 February 2010. A month later on 24 March 2010, he made his first start of the season against FC Twente in the second leg of the KNVB Cup semi–finals and helped the club win 2–1 to reach the
final. Later in the 2009–10 season, Castaignos would make two more appearances and the club would finish in fourth place. The 2010–11 season campaign proved to be Castaignos' breakout season, stemming from squad rotation and losses in the transfer market. He made his
UEFA Europa League debut, coming on as a 77th-minute substitute, in a 1–0 win against
Gent in the first leg of the play-off rounds (as Feyenoord went on to lose 2–0 in the return leg and was eliminated from the tournament). Following the club's elimination in the UEFA Europa League, Castaignos scored his first career goal for Feyenoord, in a 4–0 win against
Vitesse on 28 August 2010. As a result, the club began talks with the player over a new contract. However, he rejected a contract extension, leaving his future at Feyenoord uncertain. Amid to the contract rejection, he scored three goals in three matches between 31 October 2010 and 14 November 2010 against
AZ Alkmaar,
Roda JC and
SC Heerenveen. Castaignos changed his mind when he signed a contract extension with the club, keeping him until 2013, but his agent disputed the claims that the deal was done. Castaignos later scored two more goals by the end of the year, coming against
ADO Den Haag on 28 November 2010 and SBV Excelsior on 11 December 2010. In a friendly match against
Sparta Rotterdam on 5 January 2011, he received a straight red card in the 57th minute for kicking an opponent, in a 4–2 win. After the match, Castaignos was investigated for his actions by the KNVB, but no action was taken against him. During the same month, he suffered ankle injury while training but quickly recovered from the injury. A month later against Vitesse on 6 February 2011, Castaignos scored his seventh goal of the season, in a 1–1 draw. Two weeks later on 20 February 2011, he scored his first brace of his career, in a 2–2 draw against ADO Den Haag. Two weeks later on 6 March 2011, Castaignos scored his tenth goal of the season, in a 1–0 win against SC Heerenveen. This was followed up by scoring his eleventh goal of the season, in a 2–1 win against
NAC Breda. He went on to score four goals in the last four matches of the season that saw Feyenoord finish 10th place in the league, missing out on the Europa League in the process. At the end of the 2010–11 season, Castaignos went on to make 37 appearances and scoring fifteen times in all competitions. He later said in an interview about his desire on returning to Feyenoord one day.
Inter Milan As a result of rejecting a new contract with Feyenoord, Castaignos was on the rampant speculation during the January transfer window, with Italian giants
Inter Milan,
PSV Eindhoven,
Tottenham Hotspur and
Valencia were interested in signing the player. In the January transfer window, Inter Milan had their €3 million bid rejected by Feyenoord for Castaignos. After months of agreement, it was finally announced on 4 March 2011 by Feyenoord that the club had agreed to terms with Inter Milan, selling the player for a fee believed to be around €3 million upon the completions of the 2010–2011 season. Upon joining the club, he said: "As a striker you always want to score, but I had hoped to say goodbye with European football. The choice for Inter was a choice based on feeling. I hope that I can become a better football player there. Of course I am really looking forward to going in that direction and developing myself as footballer. I want to become a top player." Castaignos was featured throughout preseason, most notably scoring the opening goal in a friendly against Celtic on 30 July 2011. He made his competitive debut for Inter Milan in a
Supercoppa Italiana, coming on for
Joel Obi in a 2–1 loss against
Milan, and played in front of 70,000 people at
Beijing National Stadium, Beijing
China PR. However, Castaignos was controversially dropped from the
UEFA Champions League squad. This led the club's chairman
Massimo Moratti commenting on the situation on the player, saying: "I was very sorry for Castaignos because he is a great guy, if this story came up he would play him. It's pretty bad, but it's not like you hit someone. We just have to avoid these things." Despite hops of his inclusion in the squad for the tournament, Castaignos remained out of the squad. He made his full league debut, starting a match before being substituted at half time, in a 3–1 loss against
Novara on 20 September 2011. Castaignos then scored his first goal in
Serie A in an away match to Siena on 27 November 2011, latching on to
Thiago Motta's through ball before firing low past
Brkić, which proved to be the game winner. However, Castaignos found his first team opportunities limited, due to competitions in the striker positions. As a result of his lack of first team opportunities, Castaignos was linked a move away from the club, as European clubs from Italy and his homeland country, including PSV Eindhoven were interested in signing him. Ultimately, he stayed at Inter Milan after his agent ruled out of suggestions about the player being loaned out. During a 3–0 loss against
Bologna on 17 February 2012, Castaignos was involved in altercation with
Andrea Raggi after he spat on Raggi in the 85th minute. After the match, Serie A officials reviewed footage of the incident and he was subsequently banned for three matches. Even after serving a three match suspension, his actions caused Inter to immediately move him into a reserve role, scoring twice in three appearances for the reserve squad and only playing once in the league. However, Castaignos then suffered a hamstring injury, missing out for the rest of the season during a match against
Padova Primavera on 4 April 2012 and was sidelined for the rest of the 2011–12 season. At the end of the 2011–12 season, he went on to make eight appearances and scoring once in all competitions. Following this, his future at Inter Milan was uncertain when Castaignos was linked with a move away from the club. It came after when he was linked with a move to clubs around
Premier League clubs, such as,
Liverpool,
West Ham United,
Everton and even his former club, Feyenoord. On 20 June 2012, Castaignos announced his intention to leave
Inter in favor of a 'big club'.
FC Twente On 28 July 2012, Castaignos made his return to the Eredivisie when
FC Twente agreed to terms with
Inter Milan for €6 million. The move was confirmed on 30 July 2012 when he signed a four–year contract with the club and was given a number thirty shirt. Castaignos was seen as the replacement for the former Twente striker
Luuk de Jong, who had been sold to
Borussia Mönchengladbach. Castaignos made his debut for FC Twente, coming on as a 70th-minute substitute for
Dmitri Bulykin, in a 4–1 win over
FC Groningen in the opening game of the season. On 26 August 2012, he scored his first goal for the club and set up a goal for
Dmitri Bulykin in a 3–1 win over
NEC Nijmegen. Four days later on 30 August 2012, Castaignos helped FC Twente when he set up a goal for
Felipe Gutiérrez, in a 4–1 win against
Bursaspor in the second leg of the UEFA Europa League play-off round and helping the club progress to the group stage. Since joining FC Twente, Castaignos quickly established himself as the club's first choice striker and was living up to his potential as De Jong's successor. His second goal for Twente came on 15 September 2012, in a 6–2 win against
Willem II. He then scored two goals in two matches between 7 October 2012 and 20 October 2012 against AZ Alkmaar and Roda JC respectively. In a match against
FC Den Bosch in the third round of the KNVB Cup on 30 October 2012, Castaignos set up the club's only goal of the game, but was sent–off for a second bookable offence, in a 2–1 loss. Although his suspension only effect on the KNVB Cup and went on to serve a suspension the following season, he scored his fifth goal of the season, in a 3–0 win against his former club, Feyenoord on 4 November 2012. By the end of the year, Castaignos scored four more goals, including two goals in two matches between 14 December 2012 and 21 December 2012 against
Heracles Almelo and AZ Alkmaar respectively. He had to wait until on 17 March 2013 to score his tenth goal of the season, in a 3–0 win against FC Groningen. Castaignos later scored four more goals later in the 2012–13 season, including two goals in two matches between 21 April 2013 and 28 April 2013 against
VVV-Venlo and NEC Nijmegen. He was featured in four matches in the
play-offs spot for the
UEFA Europa League next season, as FC Twente lost 3–2 against
FC Utrecht in the final. Despite suffering one injury throughout the 2012–13 season, Castaignos went on to make 44 appearances and scoring fourteen times in all competitions, making him the league's top scorer for the club. At the start of the 2013–14 season, Castaignos started the season well for FC Twente when he scored against Feyenoord on 11 August 2013 and twice against FC Utrecht in a follow–up match. Since the start of the 2013–14 season, he continued to established himself as the club's first choice striker. During a 2–2 draw against PSV Eindhoven on 14 September 2013 in which Castaignos set up two goals, he was involved in an altercation with
Stijn Schaars once the match was full time, leading to a scuffle involving several players. After the match, it was announced that Castaignos would not face charges by the KNVB. He scored three goals in three matches between 4 October 2013 and 26 October 2013 against
SC Cambuur,
Ajax and ADO Den Haag. After quickly recovering from a head injury while on international duty, Castaignos scored two goals in two matches between 24 November 2013 and 29 November 2013 against NAC Breda and Roda JC respectively. He scored four goals in four matches between 14 December 2013 and 2 February 2014. Castaignos scored two goals in two matches between 15 February 2014 and 23 February 2014 against Vitesse and Feyenoord. He played every league match until being suspended for one match for picking a yellow card during a 1–0 loss against
Go Ahead Eagles on 9 March 2014. After serving a one match suspension, Castaignos made his return to the starting line–up against Ajax on 30 March 2014 and played 70 minutes before being substituted, in a 3–0 loss. However, his return was short–lived when he was sent–off in the 88th minute, in a 1–1 draw against ADO Den Haag on 2 April 2014. After serving a two match suspension, Castaignos returned to the starting line–up against NEC Nijmegen on 27 April 2014 and helped FC Twente qualify for the
UEFA Europa League next season. At the end of the 2013–14 season, he went on to make 31 appearances and scoring fourteen times in all competitions. Ahead of the 2014–15 season, Castaignos was linked with a move to
Bundesliga side
Bayer Leverkusen and
Premier League side
Swansea City. But he ended up staying at the club throughout the summer transfer window. At the start of the 2014–15 season, Castaignos continued to established himself as FC Twente's first choice striker. He scored two goals in two matches between 24 August 2014 and 28 August 2014 against NAC Breda and
Qarabağ respectively. His goal scoring form throughout September was added to a total of six, including scoring two consecutive goals against Heracles Almelo and
Achilles '29. A month later on 26 October 2014, Castaignos scored his ninth goal of the season, in a 2–1 loss against SBV Excelsior. He then scored three more goals between 23 November 2014 and 30 November 2014, including a brace against
PEC Zwolle. However, Castaignos suffered a setback when he suffered an eye injury and was sidelined for a month. Castaignos previously suffered a hamstring injury two months prior while on international duty but he quickly recovered. Castaignos returned to the starting line–up against his former club, Feyenoord on 17 January 2015, as the club lost 3–1. Ten days later on 27 January 2015, he scored his thirteenth goal of the season, in a 3–0 win against AZ Alkmaar in the quarter–finals of the KNVB Cup. On 28 February 2015, Castaignos scored his fourteenth goal of the season, in a 1–1 draw against NAC Breda. However, during a 2–0 win against PEC Zwolle on 14 March 2015, he suffered a hamstring injury and was substituted at half time. After missing two matches, Castaignos returned to the first team from injury, coming on as a 71st-minute substitute, in a 3–1 win against Go Ahead Eagles on 12 April 2015. At the end of the 2014–15 season, he went on to make 35 appearances and scoring fourteen times in all competitions.
Eintracht Frankfurt After three prolific seasons at Twente, Castaignos was expected to leave FC Twente in the summer transfer window, due to the club's financial problems. As a result, he was linked with a move to Swansea City and
Bundesliga outfit
Eintracht Frankfurt. On 29 June 2015, it was reported that Eintracht Frankfurt agreed to sign Castaignos for a reported €4 million move. The move was confirmed the next day, with the player signed a three–year contract with the club. However, the transfer fee was disputed, as it cost whether €2.5 million and €4 million. This threatened to cause him to miss the start of the 2015–16 season by being sidelined between two and four weeks. But Castaignos quickly made a full recovery from a thigh injury. He made his debut for the club in the first round of the DFB–Pokal against
Bremer SV on 8 August 2015 and scored his first goal for Eintracht Frankfurt, in a 3–0 win. Castaignos scored two braces in two matches between 29 August 2015 and 12 September 2015, winning both matches against
VfB Stuttgart and
1. FC Köln. Since joining the club, he quickly become involved in the first team, becoming Eintracht Frankfurt's first choice striker with
Haris Seferovic. After a promising start at the club, Castaignos' performance was criticised due to not scoring regularly and was demoted to the substitute bench as a result. However, Castaignos suffered ankle injury during a match against
Bayer Leverkusen on 21 November 2015 and was substituted in the 22nd minute, as Eintracht Frankfurt lost 3–1. After the match, it was announced that the player would be sidelined for three months. Following his return from injury, Castaignos continued to be relegated to the bench in the second part of the season, as well as, his goal drought. He played in the first leg of the Bundesliga play-offs against
1. FC Nürnberg as the late substitute and the club went on to win 2–1 on aggregate to avoid relegation. At the end of the 2015–16 season, Castaignos went on to make 21 appearances and scoring five times in all competitions. Ahead of the 2016–17 season, Castaignos was expected to stay at Eintracht Frankfurt. It came after when
Galatasaray,
Sporting CP,
Newcastle United and
Southampton. He made first and only appearance for the club against
1. FC Magdeburg in the first round of the DFB–Pokal. With his first opportunities at Eintracht Frankfurt, it was expected that Castaignos would be leaving the club.
Sporting CP In summer 2016, Castaignos joined compatriot
Bas Dost at Portuguese side
Sporting CP on a three-year deal. The transfer move reported to have cost €2.5 million and a
buyout clause of €60 million. Upon joining the club, he was given a number twenty shirt. Castaignos made his long-awaited debut for Sporting CP, coming on as a 61st-minute substitute, in a 1–1 draw against
Tondela on 22 October 2016. He was handed his first start for Sporting only on 2 November 2016, in a Champions League match against
Borussia Dortmund and 45 minutes before being substituted, in a 1–0 loss. However, Castaignos found his first team opportunities limited and found his playing time, coming from the substitute bench. He also found himself plagued with injuries along the way. At the end of the 2016–17 season, Castaignos made thirteen appearances in all competitions. Following this, Publico named the player as one of the club's worst signing of the season. Following his loan spell at Vitesse came to an end, Castaignos was featured in Sporting CP's pre–season squad. He continued to expect to leave the club over the summer despite making his return. Amid the transfer speculation, Castaignos made his appearance for Sporting CP in over a year, coming on as a late substitute, in a 1–1 draw against
rivals,
Benfica on 25 August 2018. Eventually, he ended up staying at the club when the transfer window closed. Following this, Castaignos continued to find his first team opportunities limited and was placed on the substitute bench. He went on to make three appearances for the club in the 2018–19 season. It was announced on 19 February 2019 that Castaignos left Sporting CP by mutual consent after months of speculation over his future at the club. It was reported in the Portuguese media that Castaignos cost Sporting CP10,000 euros for every minutes he played in the competition.
Vitesse (loan) On 7 August 2017, Castaignos returned to the Netherlands to join
Vitesse on a season-long loan. It came after when Sporting CP expected the player to leave in the summer. He made his debut for the club, coming on as a 78th-minute substitute, in a 4–1 win against NAC Breda in the opening game of the season. Since joining Vitesse, Castaignos found his playing time, coming on from the substitute bench and competed with
Tim Matavž over the first choice striker role. He spoke out about his place in the first team, saying: "I had to be patient, waited a long time. But everything is happening as it should happen. In moments like this I have to take my chance." Castaignos then scored his first goal for the club, in a 3–0 win against Excelsior on 9 September 2017. However, he suffered a concussion in a match against
Zulte Waregem in the UEFA Europa League match on 2 November 2017 and was substituted in the 35th minute, as the club lost 2–0. After missing one match, Castaignos returned to the first team from injury, coming on as an 83rd-minute substitute, in a 4–2 loss against FC Groningen on 19 November 2017. Three weeks later on 7 December 2017, he scored his second goal for Vitesse, in a 1–0 win against
OGC Nice in the UEFA Europa League Group Stage. After going two months without scoring, Castaignos finally scored his third goal for the club, in a 2–1 loss against Excelsior on 17 February 2018. He played in both legs of the
play-off against FC Utrecht and helped Vitesse win 5–3 on aggregate to qualify for the
UEFA Europa League next season. At the end of the 2017–18 season, Castaignos went on to make 36 appearances and scoring three times in all competitions. Following this, he returned to his parent club.
Gyeongnam FC On 20 February 2019, Castaignos officially joined South Korean
K League 1 football club
Gyeongnam FC. Upon joining the club, he said: "I am delighted to be joining Gyeongnam. I am looking forward to living in Gyeongnam, and I want to meet the fans at the stadium as soon as possible. " In a follow–up match against
Shandong Luneng in the
AFC Champions League, he set up a goal for
Kim Seung-jun, in a 2–2 draw. However, Castaignos suffered a knee injury and was substituted at half time, as Gyeongnam won 2–1 against
Daegu on 30 March 2019. As a result, he was sidelined for two months. Castaignos made his return from injury against
Johor Darul Ta'zim on 22 May 2019 and scored his first goal for the club, in a 2–0 win. After missing a match due to being given a personal leave, he scored two goals in two matches between 15 June 2019 and 22 June 2019 against Seongnam and
Incheon United. After suffering another injury, Castaignos then scored his fourth goal for Gyeongnam, in a 2–2 draw against
Jeju United on 22 July 2019. Despite the injuries, he continued to remain involved in the first team throughout the 2019 season. However, the club ended up relegated to
K League 2 after losing 2–0 to
Busan IPark on aggregate on 8 December 2019. At the end of the 2019 season, Castaignos made 26 appearances and scoring four times in all competitions. However,
the 2020 season was pushed back to May because of the
pandemic. He also stayed at Gyeongnam despite the club's relegation. Castaignos made his first appearance of the season, coming on as 78th-minute substitute, in a 0–0 draw against
Ansan Greeners on 20 July 2020. In a follow–up match against
Jeonnam Dragons, he scored his first goal of the season, in a 1–1 draw. Castaignos scored his second goal of the season, in a 3–3 draw against Jeju United on 5 September 2020, in what turned out to be his last appearance for Gyeongnam. On 21 September 2020, the club announced that they have terminated his contract by mutual consent, with manager
Seol Ki-hyeon claiming that the player fell out with the management. By the time he departed from Gyeongnam, Castaignos made eight appearances and scoring two times in all competitions.
OFI On 21 January 2021, Castaignos agreed a move to Greek club
OFI. The move was confirmed on 25 January 2021, with the player signed a two–year contract, keeping him until 2023. Upon joining the club, he said: "I was surprised by the way I played with total football." Castaignos made his debut for OFI, coming on as an 82nd-minute substitute, in a 2–0 loss against
AEK Athens on 31 January 2021. He then scored his first goal for the club, in a 2–1 loss against
Volos two weeks later on 14 February 2021. However, Castaignos suffered a leg injury that saw him sidelined between four and six weeks. But he made his return from injury, coming on as a second-half substitute, in a 2–2 draw against
Panetolikos in the last game of the season. At the end of the 2020–21 season, Castaignos made eight appearances and scoring once in all competitions.
1. FC Magdeburg Castaignos joined
2. Bundesliga club
1. FC Magdeburg as a
free agent in January 2023, after a trial. He left Magdeburg at the end of the 2023–24 season. ==International career==