Minor leagues The
Detroit Tigers selected Castellanos in the first round, with the 44th overall pick, in the
2010 Major League Baseball draft. He was rated by
Baseball America as the third best power hitting prospect and fourteenth best overall prospect prior to the draft. He signed with the Tigers, receiving a $3.45 million
signing bonus, the highest bonus at that point ever given to a player taken after the first round. The deal was almost invalidated, as the Tigers' email to the office of
Commissioner of Baseball Bud Selig was not received until three minutes after the midnight deadline on August 15, 2010; a
text message about the deal to Selig's office received at 11:59 convinced Selig to approve the deal. Though Castellanos played
shortstop in high school, the Tigers shifted him to
third base as a professional. Castellanos appeared in seven games for the
Gulf Coast Tigers of the Rookie-level
Gulf Coast League that season. Before the 2011 season,
Baseball America rated Castellanos as the 65th-best prospect in baseball. He played for the
West Michigan Whitecaps of the Class-A
Midwest League. With the Whitecaps, Castellanos batted .312 with seven
home runs and 76 RBIs, in 2012 Prior to the 2012 season,
Baseball America ranked him as the second best prospect in the organization and 45th best in baseball. The Tigers invited Castellanos to
spring training in 2012, and expected to assign him to either the Class-A Advanced
Lakeland Tigers of the
Florida State League or the Class-AA
Erie SeaWolves of the
Eastern League. Castellanos began the 2012 season with Class-A Lakeland. He was named the Tigers' minor league player in May 2012. After he batted .402 with 32 RBIs in 55 games for Lakeland, the Tigers promoted Castellanos to Erie on June 4. Appearing in the 2012
All-Star Futures Game, Castellanos hit a three-run home run, and was named the game's
Most Valuable Player. He batted .264 with Erie that year. Castellanos was blocked at third base by
Miguel Cabrera and at first base by
Prince Fielder. He had been seen as a potential centerpiece for a trade to acquire a marquee talent. However, the Tigers considered Castellanos untouchable in trade negotiations. Castellanos began to take
outfield practice in
left field during the 2012 season. In 134 games for the Mud Hens, Castellanos batted .276 with 18 home runs and 76 RBIs. He appeared in the
Triple-A All-Star Game and was named to the International League's post-season All-Star team.
Detroit Tigers 2013–2016 , 2012 When
major league rosters expanded on September 1, 2013, Castellanos was among the players promoted to the Tigers, On September 7, Castellanos made his first major league start, and recorded his first major league hit, an
infield single, off
Danny Duffy. However, he received infrequent playing time, as the Tigers were in a pennant race and
manager Jim Leyland preferred to use players with more major league experience. He batted 5-for-18 with the Tigers in 2013.
Dave Dombrowski, the
general manager of the Tigers at that time, said that they would shift Miguel Cabrera to first base, and use Castellanos as their starting third baseman for 2014. Castellanos hit his first MLB
home run on April 9, 2014, off the top of the wall in dead center field off
Josh Beckett of the
Los Angeles Dodgers at
Dodger Stadium. He finished his rookie season with a .259 batting average, 11 home runs, 31 doubles and 66 RBIs. He was named the 2014 Detroit Tigers/Detroit Sports Media Association Rookie of the Year. On July 22, 2015, Castellanos hit his first career
grand slam off
Mike Montgomery of the
Seattle Mariners. Castellanos hit .255 that season while slamming 15 home runs and driving in 73. Through the All-Star break of the 2016 season, Castellanos was hitting .302 with 17 home runs and 51 RBIs, while playing as the Tigers' starting third baseman. On August 6, Castellanos was struck by a pitch from
New York Mets reliever
Logan Verrett, fracturing the fifth
metacarpal bone in his left hand. After the game, Castellanos was placed on the 15-day disabled list for the first time in his career, and was expected to miss at least four weeks. Castellanos did not return to the Tigers until the final week of the regular season, entering a September 27 game against the
Cleveland Indians as a pinch hitter. During the 2016 season, Castellanos set career highs with a .285 average, 18 home runs, .331 on-base percentage, and a .496 slugging percentage, despite being limited to 110 games.
2017–2019 On January 13, 2017, the Tigers avoided arbitration with Castellanos, agreeing on a one-year contract worth $3 million. On July 18, Castellanos hit a single, triple and two home runs in a game against the
Kansas City Royals, becoming the fourth Tigers player to do so since
1913, and the first Tigers player to do so since
Dmitri Young in
2003. On September 29, Castellanos recorded his 100th RBI of the season. Castellanos became the 10th player in Tigers history to drive in more than 100 runs at the age of 25 or younger, and the first player to do so since
Miguel Cabrera in
2008. He became the sixth player in Tigers history to record 10 or more triples, 25 or more home runs, and 100 or more RBIs in a season, and the first player to do so since
Al Kaline in
1956. Castellanos finished 2017 with a .272 batting average, while setting career highs in doubles (36), triples (10), home runs (26) and RBIs (101). His 10 triples led the American League. He struggled defensively, however, as he led all third basemen with 18 errors and had a league-worst .939
fielding percentage among qualified third basemen. With the acquisition of third baseman
Jeimer Candelario and the departure of right fielder
J. D. Martinez, both in July trades, Castellanos began playing games in right field from early September to the end of the 2017 season. On January 17, 2018, the Tigers avoided arbitration with Castellanos, agreeing on a one-year contract worth $6.05 million. On August 13, Castellanos went 5-for-5 with five RBIs, for his first career five-hit game. He became the first Tigers player with five hits in a game since
Ian Kinsler in
2015. With two singles, two doubles, and a home run, he also became the first Tiger with 10 total bases in a game since
Justin Upton in
2017. Castellanos earned American League Player of the Week honors for the week of August 13–19. In seven games, he batted .393 with an OBP of .485 and had two homers, three doubles, eight runs scored, and ten RBI. The award was the first weekly honor for any Tiger player in 2018, and the first since
J.D. Martinez won the award for the week ending July 17, 2017. Castellanos hit a career-high .298 in the 2018 season, adding 23 home runs and 89 RBIs. He finished among the AL leaders in hits (185, third), doubles (46, fourth), and multi-hit games (56, third). He also led all MLB hitters (60 or more plate appearances) in batting average against left-handers, at .381. He was named the 2018 Tiger of the Year by the Detroit Chapter of the Baseball Writers' Association of America (BBWAA). On January 11, 2019, the Tigers avoided arbitration with Castellanos, agreeing on a one-year contract worth $9.95 million.
Chicago Cubs On July 31, 2019, the Tigers traded Castellanos along with cash considerations to the
Chicago Cubs in exchange for
Alex Lange and
Paul Richan. In August, Castellanos hit .348 with 11 home runs, 20 RBIs, and nine doubles to go along with a .385 on-base percentage and a .713 slugging percentage. In 51 games for the Cubs in 2019, Castellanos hit .321 with 16 home runs, 36 RBIs, and a 1.002 OPS. For the 2019 season, Castellanos had a .289 batting average, 27 home runs, 73 RBIs, and an MLB-leading 58 doubles. He also joined Hall of Famers
Hank Greenberg (1934) and
Joe Medwick (1937) as the only right-handed batters to ever hit 55 doubles and 25 home runs in the same season. On defense in 2019, he posted −9
defensive runs saved, the worst in the major leagues among right fielders, and −4.4
ultimate zone rating, second worst.
Cincinnati Reds Castellanos signed a four-year, $64 million contract with the
Cincinnati Reds on January 27, 2020. The contract included an opt-out clause. In a 2020 season shortened by the
COVID-19 pandemic, he hit just .225, with 14 home runs and 34 RBI in 60 games. On defense, Castellanos had a
fielding percentage of .963, the lowest among all major league right fielders, with −4
defensive runs saved and a −3.0
ultimate zone rating. On August 19, 2020, during the opening game of a doubleheader in
Kauffman Stadium, Reds broadcaster
Thom Brennaman was apologizing for a homophobic slur he uttered on a
hot mic earlier in the broadcast. Mid-apology, Castellanos hit a home run, and Brennaman broke from his apology to deliver the
play-by-play. Brennaman said, "I pride myself and think of myself as a man of faith, as there's
a drive into deep left field by Castellanos, it will be a home run. And so that'll make it a 4–0 ballgame." The moment, as well as
future instances of Castellanos recording hits during broadcast discussions of negative events, became an
internet meme as a
copypasta. ESPN's
Pablo S. Torre later said it "was like listening to the band play on as the
Titanic was sinking. Except the band was also somehow the iceberg." On July 5, 2021, Castellanos hit a home run at Kauffman Stadium while the
Kansas City Royals' broadcast was in the middle of a eulogy for a military veteran. Castellanos earned his first All-Star selection in 2021. By season's end, Castellanos had posted career highs in batting average (.309) and home runs (34), while driving in 100 runs. It was his second career 100-RBI season and first since 2017. Defensively, he posted an improved fielding percentage of .991, having committed only three errors, but also had −4 defensive runs saved and a −4.5 ultimate zone rating. Castellanos opted out of his contract after the 2021 season, becoming a
free agent.
Philadelphia Phillies On March 22, 2022, the
Philadelphia Phillies signed Castellanos to a five-year, $100 million contract. Castellanos again interrupted a broadcast moment in a spring training game against the
Toronto Blue Jays on March 27, when he recorded his first hit as a Philly while the Blue Jays broadcast team was discussing the DUI arrest of Toronto pitching coach
Pete Walker two days earlier. On
Memorial Day, Castellanos hit a home run just as broadcaster
Tom McCarthy had finished telling viewers about the American Gold Star Mothers Chair of Honor in
Citizens Bank Park. In 2022, Castellanos batted .263/.305/.389 in 524 at–bats. He swung at 57.0% of all pitches, the highest percentage of all major league batters. Castellanos was the final out of the
2022 World Series, fouling out to
Houston Astros right fielder
Kyle Tucker to end game 6 and clinch the series for the Astros. In the
2023 National League Division Series, Castellanos hit two home runs in each of Games 3 and 4, becoming the first player in MLB history to hit multiple home runs in consecutive postseason games. In Game 1 of the
2023 National League Championship Series, Castellanos hit a home run in his first plate appearance, joining
Reggie Jackson as the only players in postseason history to hit five home runs in a three-game span. However, he went hitless with 11 strikeouts in his final 23 at-bats as the Phillies lost in seven games to the
Arizona Diamondbacks despite having held a 2–0 series lead. Castellanos played in all 162 games for the Phillies in 2024, slashing .254/.311/.431 with 23 home runs, 86 RBI, and six stolen bases. On June 17, 2025, Castellanos was benched in the second game of the Phillies' series against the
Miami Marlins due to "inappropriate" comments, ending his streak of games started at 236. It was later revealed that he had brought a beer into the
dugout and criticized manager
Rob Thomson and the coaches after being removed from the previous day's game. Later in the season, Castellanos lost playing time, entering a
platoon with
Max Kepler. On September 19, Castellanos hit his 250th career home run. Castellanos played in 147 games for the Phillies in 2025, slashing .250/.294/.400 with 17 home runs, 72 RBI, and four stolen bases. Following the 2025 season, the Phillies unsuccessfully looked to trade Castellanos over the offseason after reports indicated that his relationship with Thomson had deteriorated following the benching incident during the prior season. On February 12, 2026, Castellanos was released by the Phillies after four seasons with the team, with the Phillies still owing Castellanos $20 million for the 2026 season.
San Diego Padres (2026–present) On February 15, 2026, Castellanos signed a one-year contract with the
San Diego Padres. The Padres intend to utilize him as a
first baseman. ==Personal life==