Cuban National Series (2007–2012) Díaz played in the
Serie Nacional de Béisbol (
Cuban National Series), the primary amateur
baseball competition in
Cuba, for the
Naranjas de Villa Clara, based in Santa Clara. He debuted in the 2007–08 season by going nine for 32 in a
utility role. At age 19 in 2008–09, Díaz
batted .301 with a .403
on-base percentage (OBP) and .482
slugging percentage (SLG) but
fielded only .930 as a regular infielder. He was third in the
Serie Nacional with 24 errors. The next season, Díaz batted .282 with a .348 OBP, .363 SLG and fielded .950 as Villa Clara's starting shortstop. He tied for fifth in the Serie Nacional with 18 errors, having improved his defense. During his 2011–12 season, Díaz' offensive production continued to climb, as he batted .315 with a .404 OBP and .500 SLG. He hit 12
home runs in 270
at bats. From 2008 to 2012, Díaz, batted .308 with a .401 OBP and .444 SLG. He
defected from Cuba in 2012 while playing with the
Cuban national baseball team in a tournament in the
Netherlands. He was declared ineligible to sign with any MLB teams until February 19, 2014, due to lying about his age. He spent the interim 18 months from defecting from Cuba playing in
Mexico City.
Minor leagues (2014–2015) To audition for a contract with MLB clubs, Díaz held a showcase with fellow Cuban defector
Odrisamer Despaigne on February 13, 2014. The Cardinals first assigned Díaz to the
Palm Beach Cardinals of the
High–A Florida State League in 2014, and he was promoted to the
Springfield Cardinals of the
Double–A Texas League that season. In 47 games between both teams, he batted .273/.324/.441 with five home runs, 24 RBIs, and seven stolen bases. In 2015, while playing for Springfield, he battled injuries before he was
designated for assignment on July 8, 2015. While he had benefited from talent alone while playing in Cuba, his lack of preparation had caused his performance to suffer after playing the minor leagues. However, he diligently began to prepare more and proactively ask more questions. In the last 45 games of the 2015 season after his removal from the
40-man roster, Díaz batted .333 with a .404 OBP and a .574 SLG. The Cardinals added him to the 40-man roster on November 19, 2015. He batted .239 against right-handed pitchers, .371 against left-handers, .329 in road games and .222 in home games. He played in the
Arizona Fall League following the regular season, registering a .616 SLG and .987 OPS.
St. Louis Cardinals (2016–2017) All-Star rookie (2016) Originally planning for Díaz to spend the 2016 season in Memphis, the Cardinals eventually moved three veteran players to accommodate him becoming the starting shortstop. On April 5,
2016, the Cardinals recalled him to the major league roster to take the place of
outfielder Tommy Pham, who had departed on
Opening Day two days earlier with an injury. Díaz debuted on the same day as his call-up. In his first major league at bat in the third inning against the
Pittsburgh Pirates, he singled off
Jon Niese for his first hit in a 6–5 loss. Initially, Díaz' presence on the roster gave the Cardinals a capable hitter with upside who could play shortstop On April 8, Díaz's first major league home run contributed to the Cardinals becoming the first team in major league history to hit three
pinch hit home runs in the same game.
Jeremy Hazelbaker and
Greg Garcia were the other pinch hitters as the Cardinals defeated the
Atlanta Braves, 7–4. The previous record of two pinch hit home runs by the same team in one game was previously accomplished on 57 occasions, most recently in 2011. Tejada was reinstated from the
disabled list on April 18, However, Díaz's hitting had led the Cardinals to instead retain him as the starting shortstop, thus assigning Tejada to be a utility infielder. In an 11–2 win over the
San Diego Padres on April 23, Díaz garnered his first five-hit game. After collecting two hits in his first two at bats in a game against the
Arizona Diamondbacks on April 25 to give him 26 hits in 52 at bats, he became the first rookie in MLB since 1900 to carry at least a .500 batting average at any point after accumulating 50 at bats, per the
Elias Sports Bureau. Meanwhile, past defensive liabilities reemerged: in Díaz' first 31 games of the season, he committed nine errors. When Peralta returned from the disabled list on June 7, Díaz' sustained level of play convinced the Cardinals to displace Peralta to
third base and third baseman
Matt Carpenter to
second base. Díaz appeared as a pinch hitter with the bases loaded against
Will Harris in the eighth inning, and struck out looking as the
American League defeated the National League, 4–2. On July 21 against Padres in a 5–5 game, Díaz batted against
Carlos Villanueva with the bases loaded in the bottom of the ninth inning and, this time, singled home the game-winning run for his first career walk-off hit. After sustaining a
hairline fracture of his thumb during a game against
Miami, the Cardinals placed Díaz on the DL on August 1. He missed all of August and the first two weeks of September. Díaz hit his first major league
grand slam on September 27, 2016, his first game back after the death of his childhood friend, José Fernández. Díaz was called back out for a curtain call, where he raised his helmet high towards the sky. He stated afterwards, "Every time I put on a uniform, I will think of him." Over his last 31 games of the season, he committed one error. Diaz began the season with a .217 batting average, and improved in the month of May. The Cardinals optioned him to Memphis on June 28, after batting .260/.293/.396, seven home runs and 20 RBIs in 71 games. He eventually lost his role as the Cardinals' starting shortstop with the emergence of rookie
Paul DeJong—who finished second in the NL Rookie of the Year balloting—as a powerful batter and capable fielder. In the final game of the 2017 season, Díaz tore his hamstring. In 2017 with the Cardinals he batted .259/.290/.392 in 286 at bats, while playing primarily shortstop.
Toronto Blue Jays (2018) The Cardinals traded Díaz to the
Toronto Blue Jays on December 1, 2017, for minor league outfielder J. B. Woodman. Díaz began the season as Toronto's starting shortstop with
Troy Tulowitzki on the
disabled list (DL). On May 8, Díaz was placed on the DL list with a left ankle sprain. To that point in the season, he had batted .216/.273/.431 with six home runs and 13 RBI over 110
plate appearances. He was activated on June 1. For the season, Díaz hit .263/.303/.453 with 18 home runs and 55 RBIs in 422 at bats in 130 games while playing primarily shortstop. During his tenure as an Astro, Díaz, who had mostly appeared at shortstop, became the team's
utility player, and started at three new positions in the major leagues –
second base,
first base, and
left field. In
2019, he batted .271/.356/.467 with nine home runs and 40 RBIs in 210 at bats. During the 2021 regular season, he batted .259/.317/.405 with eight home runs and 45 RBIs in 294 at bats.
2022 Díaz avoided arbitration with the Astros on March 22,
2022, agreeing to a $4.45 million contract for the season. On May 8, 2022, Díaz hit a grand slam versus the
Detroit Tigers to lead a 5–0 Astros win. He started at third base and homered on June 4 to help lead a 10–3 win over the
Kansas City Royals, and added two singles for his first three-hit game of the season. Díaz singled and scored in the ninth on July 12 versus the
Los Angeles Angels to catalyze a four run comeback after hitting an early two-run home run and walking twice. He homered twice on July 29 versus the
Seattle Mariners to help fuel an 11–1 rout. On August 6, Díaz started at shortstop versus
Cleveland, doubling twice and driving in one run. Díaz hit his second grand slam of the season versus
Martín Pérez of the
Texas Rangers on August 9, bringing the Astros back from a 4–0 deficit to result in a 7–5 win. On August 16, Díaz exited a game versus the
Chicago White Sox due to a groin injury, and was placed on the 10-day injured list the following day. He was activated on September 13. In 2022 he batted .243/.287/.403 in 305 at bats with 12 home runs and 38 RBIs in 305 at bats. Following the World Series, Díaz became a free agent.
Oakland Athletics On December 13, 2022, Díaz signed a two-year contract with the
Oakland Athletics. In 2023, he appeared in 109 games, including 40 at both third base and shortstop. It was the highest number of games played for Díaz since 2018. He hit .229 with 4 home runs and 24 RBI. He had career lows in batting average,
on-base plus slugging (OPS), and
slugging percentage. He was the highest paid position player on the team with an annual salary of $6.5 million. During spring training prior to the
2024 season, Díaz suffered a groin strain. While rehabbing, he suffered a calf strain. The injuries kept him off the field for most of the Athletics spring training, and he was placed on the 60–day injured list to begin the season. On May 27, 2024, Díaz was activated off of the injured list. In 12 games for the Athletics, he went 3–for–29 (.103) with no home runs and one RBI. On July 2, Díaz was
designated for assignment by Oakland. He was released by the organization on July 5.
Houston Astros (second stint) On July 13, 2024, Díaz signed a minor league contract with the
Houston Astros. In four games with the rookie–level
Florida Complex League Astros, he batted .333 with two RBI. On July 22, Houston selected Díaz's contract, adding him to their major league roster. In his first game with the Astros since 2022, Díaz went 0-3 with a strikeout. Díaz was released by the Astros following the promotion of
Shay Whitcomb on August 16.
Leones de Yucatán On March 20, 2025, Díaz signed with the
Leones de Yucatán of the
Mexican League. In 53 appearances for Yucatán, he batted .254/.316/.468 with 11 home runs and 37 RBI. Díaz was released by the Leones on July 11.
Tecolotes de los Dos Laredos On July 11, 2025, Díaz signed with the
Tecolotes de los Dos Laredos of the
Mexican League. In 22 appearances for Dos Laredos, he batted .341/.379/.568 with five home runs, 17 RBI, and one stolen base. On April 10, 2026, Díaz was released by the Tecolotes. ==Personal life==