Minor leagues Flores signed as an international
free agent with the New York Mets on August 6, 2007, his 16th birthday. With his $750,000
signing bonus, he bought his mother a new
Hyundai Sonata he did not know how to drive. He also appeared in the All-Star Futures Game for the second time in his career. The Mets promoted Flores to the
Binghamton Mets of the
Double–A Eastern League during the 2012 season. He finished the 2012 season with Binghamton batting .311/.361/.494 in 66 games with eight home runs, 33 RBI, and 20 walks. Flores began the 2013 season with the
Las Vegas 51s of the
Triple–A Pacific Coast League. He finished batting .321/.357/.531 in 107 games with 15 home runs, 86 RBI, and 25 walks.
New York Mets (2013–2018) 2013 He obtained a promotion to the Mets' major league roster on August 6, his 22nd birthday. Pitcher
Bobby Parnell was placed on the disabled list with a herniated disk in his neck, a roster spot filled by Flores. He made his debut that day against the
Colorado Rockies at
Citi Field, going 0-for-4 at the plate and committing an error in the sixth inning, in what would be a 3–2 Mets win. On August 7, he notched his first career major league hit, a single in the bottom of the second inning off Rockies pitcher
Jhoulys Chacín. In the bottom of the eight inning, he hit a base clearing double off pitcher
Manny Corpas for his first three major league RBI. The Mets would go on to win 5–0. On August 11, he hit his first career home run, a solo home run to right field off
Arizona Diamondbacks pitcher
Heath Bell in the top of the ninth inning, to extend the Mets lead to 9–5, which became the final score. He finished the 2013 season appearing in 27 games, with a batting average of .211 in 95 at-bats and 101 plate appearances, while compiling 20 hits, 13 RBI, one home run, five walks, eight runs scored, and striking out 23 times.
2014 Flores started the 2014 season with the Las Vegas 51s in AAA, but was called up April 2 along with
Kyle Farnsworth in order to replace Bobby Parnell going to the disabled list and with
Daniel Murphy on paternity leave. He would be re-sent back to the 51s on April 6 to make room for
Jon Niese coming off the disabled list. Flores had only started one game, playing second base while going 0-for-4 with two strikeouts. He was recalled on May 9, with
Omar Quintanilla being designated for assignment. On June 2, Flores drove in a career high 6 RBI during which he also hit his first career
grand slam against the
Philadelphia Phillies at
Citizens Bank Park. The grand slam came in the top of the ninth inning off pitcher
Phillippe Aumont with two outs, extending the lead to 11–2. On June 26, Flores was once again re-sent down to the 51s to make room for
Juan Lagares coming off the disabled list. He was recalled for good on July 24, with
Kirk Nieuwenhuis being sent to the 51s. Flores finished the 2014 season appearing in 78 games with a batting average of .251 in 259 at-bats in 274 plate appearances while compiling 65 hits, 29 RBI, 6 home runs, 12 walks, 28 runs scored and striking out 31 times.
2015 on August 18, 2015. Flores made the Mets' roster for
Opening Day in 2015. During the first week of the season, Flores struggled offensively and defensively as he made three errors and batted .158 in seven games. In nine games after the opening week, Flores batted .364 with three home runs. Soon thereafter, Flores was tied for third in all of baseball in errors committed, with six. On May 16, Flores became the first National League
position player to hit a grand slam batting ninth in a National League ballpark. The home run came off
Milwaukee Brewers pitcher
Matt Garza at
Citi Field. It was his second career grand slam. On May 26, Flores was tied for most home runs hit by a shortstop with
Jhonny Peralta of the
St. Louis Cardinals with seven. That same day, Flores hit his first career walk-off, a single, off Phillies' pitcher
Elvis Araújo in the bottom of the tenth inning with two outs scoring Juan Lagares for his second RBI of the game. On July 29, rumors spread during a game against the
San Diego Padres that Flores had been traded to the Milwaukee Brewers, along with pitcher
Zack Wheeler, for
Carlos Gómez. Despite the rumors, Flores remained in the game, and was visibly emotional when he returned to the field as fans began to give him a standing ovation. Flores later explained his disappointment in learning that he would be leaving the only baseball organization he has ever known. However, following the game, General Manager
Sandy Alderson informed the media that no trade had occurred, stating that "social media got ahead of the facts". After the game, Mets' manager
Terry Collins told the media that he knew nothing about the potential trade, and had told Flores while the events played out, "Listen, I don't know what's going on, but you've got a game to play, let's play baseball." It was later reported that the Mets backed out of the trade after a concern about Gómez's physical as a medical report showed an issue with his hip. Two days later, on July 31, Flores hit his first career
walk-off home run, a solo home run, off
Washington Nationals pitcher
Felipe Rivero. It occurred in the bottom of the 12th inning, on a 1–1 count with no outs, winning an important game for the Mets by a score of 2–1. As Flores approached home plate finishing his circle around the bases, he memorably tugged enthusiastically at the "Mets" logo on his uniform front, signifying how happy he was to have remained with the team. Flores had also driven in the other Mets' run earlier in the game. During each at-bat, Flores received a standing ovation from the Mets' fans. The win brought the Mets within two games of first place in the
NL East. After the incident, Flores became a fan-favorite of Mets fans and was given standing ovations in the subsequent weeks, both at home and at away games. It was also the only walk-off home run the Mets hit during the 2015 season. At this point on August 25, since the failed trade, he hit .343 with a .993 OPS and four home runs. The Mets went 16–6 after that day. Flores finished the 2015 season appearing in 137 games with a batting average of .263 in 483 at-bats in 510 plate appearances. He compiled 127 hits, 16 home runs, 59 RBI, 55 runs scored, 19 walks, and struck out 63 times. His walk percentage of 3.7% was in the bottom 4% of MLB players. In the
NLDS against the
Los Angeles Dodgers, Flores hit .300 in four games, compiling three hits, one double, two walks, two runs scored, and striking out four times. Then, playing against the
Chicago Cubs in the
NLCS, he batted .286 in four games compiling four hits, one double, one triple, one walk, one stolen base, and striking out two times. During the series against the Dodgers, Mets' shortstop
Ruben Tejada was injured by the Dodgers'
Chase Utley. The injury occurred with a controversial slide, thought dirty by many, and resulted in a broken leg for Tejada. Flores played shortstop for the remainder of the postseason. Once he moved to the more important defensive position, Flores played fine defense, but struggled hitting. He was the last out of the
World Series, striking out looking in game five against
Kansas City Royals closer
Wade Davis, to clinch the series for the Royals. Flores appeared in all five games, batting .059 with one hit, one runs scored, two walks, and three strikeouts. In December, Flores suffered a broken left ankle after being hit by a pitch in winter ball in Venezuela.
2016 in 2016 On May 12, Flores was put on the 15-day disabled list with a left
hamstring injury, with his spot on the roster being taken by
Sean Gilmartin. Flores was batting .180 with one home run and two RBI in 50 at-bats playing at first, second, and third base filling in as a defensive replacement for
Lucas Duda,
Neil Walker, and
David Wright respectively. Flores was activated from the DL on May 29, with
Matt Reynolds being sent down to make room for him on the roster. In five rehab games with the
Binghamton Mets, Flores had batted .235 with one RBI and four hits. On July 3, in a home game against the Cubs, Flores became only the second Mets player to collect six hits in a game, the first being fellow Venezuelan infielder
Edgardo Alfonzo, who did so in August 1999. In doing so, he raised his batting average 31 points from .224 to .255. He became the first player in Major League Baseball to accomplish the feat since
C. J. Cron the day earlier and the first player in the National League to do so since
Charlie Blackmon on April 4, 2014. On September 10, Flores injured his wrist in a collision at home plate with
Atlanta Braves catcher A. J. Pierzynski. On September 30, the Mets announced that Flores would miss the rest of the year, including the postseason. On October 7, Flores underwent surgery to have part of the
hamate bone in his wrist removed. In 2016 he batted .267/.319/.469.
2017 On April 21, the Mets placed Flores on the 10-day disabled list with an infection in his knee which required hospitalization and
IV treatment. Flores broke his nose on a foul-tip in the second game of a double-header against the
Houston Astros on September 2, which ended his season. For his 2017 campaign, Flores finished batting .271/.307/.488 with 18 home runs and 52 runs batted in in 336 at-bats. On defense, while primarily playing third base, he had an "outs above average" rating of -9, in the bottom 4% of MLB players.
2018 On April 15, 2018, Flores hit a walk-off home run to give the Mets a win against the Brewers. This was his third career walk-off home run. On June 26, Flores drove in the winning run against the
Pittsburgh Pirates in the bottom of the 10th inning, giving the Mets a 4–3 victory. Earlier in the game, he had driven in the Mets' first two runs as well. Flores's game winner was his 9th walk-off RBI of his young career. He tied
David Wright for the most walk-off RBI in Mets' history. On July 9, in the first game of a doubleheader against the
Philadelphia Phillies, Flores hit a pinch-hit walk-off home run, breaking Wright's record for the most walk-off RBI of any player in Mets franchise history. In 2018, he batted .267/.319/.417. He struck out only 9.8% of the time, in the best 2% of MLB players.
Arizona Diamondbacks (2019) On January 21, 2019, Flores signed a one-year, $4.25 million contract with the
Arizona Diamondbacks. He played in 89 games for the Diamondbacks in 2019, hitting .317/.361/.487 with 9 home runs and 37 RBI in 265 at-bats. On September 9, Flores hit a home run off of former teammate
Jacob deGrom in his return to
Citi Field and was met with cheers. Flores also received a homecoming video from the team before the game, the first player to receive one since
Daniel Murphy in 2016.
San Francisco Giants (2020–2025) 2020 On February 4, 2020, Flores signed a two-year, $6 million contract including a third-year option with the
San Francisco Giants. In the COVID-shortened 2020 season, Flores led the team in home runs with 12 and finished second on the team in RBI (32) and runs (30), as he batted .268/.315/.515 in 198 at-bats. He played 61 games at second base, 45 at first base, 34 at third base, and 26 at DH. Flores received the
Willie Mac Award on September 30, voted on annually by Giants teammates, coaches, trainers, and fans for performance on the field and off the field.
2023 Flores played in 126 games for San Francisco in 2023, slashing .284/.355/.509 with a career–high 23 home runs and 60 RBI.
2024 Flores played in 71 games for San Francisco in 2024, batting .206/.277/.318 with four home runs and 26 RBI. On August 6, 2024, manager
Bob Melvin announced that Flores would miss the remainder of the season after undergoing a Tenex procedure to treat right
knee tendinitis. On November 2, 2024, Flores exercised his option clause, allowing him to remain with the team.
2025 On May 16, 2025, Flores had his first career three-home run game, including his seventh career
grand slam, and scored a career-high eight RBI against the
Athletics. Flores became the first Giants player to record at least 40 RBI through the team's first 45 games since
Barry Bonds in 2001 (45). Flores made 125 appearances for San Francisco, slashing .241/.307/.379 with 16 home runs and 71 RBI.
Toros de Tijuana (2026–present) On March 19, 2026, Flores signed with the
Toros de Tijuana of the
Mexican League. == Personal life ==