Gyorko was born on September 23, 1988, in Morgantown, West Virginia, to Randall and Penny Gyorko. His family also had a home on Cheat Lake, where he stayed often in his youth. He was a fan of the Pittsburgh Pirates of Major League Baseball (MLB).

Gyorko batted .100 in July, but he improved his on-base percentage and on-base plus slugging in August, and passed Gattis with 16 home runs. He continued to swing at pitches outside of the strike zone and not draw enough walks. Gyorko finished the season as the team leader in both home runs (23) and RBIs (63). He led all MLB rookies that season in OBP (.301), SLG (.444), and home runs, and his home run total was the third-most ever by an MLB rookie second baseman. He broke the Padres’ record for home runs by a second baseman, passing Bret Boone’s 19 in 2000. Gyorko was also the first MLB rookie second baseman to lead his team in RBIs. Additionally, he became just the second rookie to lead the Padres in either category since Nate Colbert in San Diego’s inaugural season in 1969. He was named to Baseball America’s All-Rookie Team, and finished sixth in NL Rookie of the Year balloting.

Gyorko attended University High School in Morgantown. He played for the school’s baseball, American football, and basketball teams. He was an infielder for the baseball team, but primarily played shortstop. In baseball, Gyorko was named to the All-Conference team all four years of his high school career. He was also named to the All-State team three times. Gyorko also played American Legion baseball for four years. He led his American Legion teams to state championships in 2004 and 2007.

Prior to Gyorko’s junior season, in 2010, he was named the preseason Big East Player of the Year and a Third Team All-American by Baseball America. Continuing to play as a shortstop, Gyorko batted .381 with 19 home runs and 57 RBIs in his junior year. He won the 2010 Brooks Wallace Award as the best shortstop in NCAA Division I. By the end of his junior season, Gyorko established himself as the Mountaineers career leader in batting average (.404), doubles (73), extra-base hits (113) and the single-season leader in walks (43), doubles (28), extra-base hits (48), and total bases (192). He also tied the WVU records for career home runs (35) and single-season home runs (19). Gyorko was considered a potential first or second round pick in the MLB Draft following his junior year, Though he had one more year of eligibility remaining at West Virginia, Gyorko said “it has always been my dream to play professionally” and that he would “go and play for a living” after his junior year.

Gyorko married his wife Karley in 2011. While he played with the Padres, the couple lived within walking distance of Petco Park, the home stadium of the Padres, during the season, and returned to Morgantown during the offseason. Karley gave birth to twin sons in April 2014. They were born premature, and one remained in the hospital for a few extra days for observation. The couple’s third child, a daughter, was born in May 2017.

The Padres invited him to spring training in 2013, giving him a chance to win a job as the starting second baseman for the 2013 Padres. Gyorko impressed Padres’ manager Bud Black with his hitting ability and defense at second base. With injuries to infielders Chase Headley and Logan Forsythe, Gyorko made the Padres’ Opening Day roster, with the opportunity to alternate between second and third base. In his MLB debut, on April 1, 2013, Gyorko started at second base, but later shifted to third base. He also recorded his first MLB hit, a double off of Jonathan Niese. He hit his first major league home run off of Scott Feldman of the Chicago Cubs on May 1, 2013. His six home runs in May tied Evan Gattis for the most among MLB rookies. Gyorko had a .280 batting average through June 10, and missed the next 30 games due to a groin injury.

Going into spring training in 2014, Gyorko began focusing on improving his plate discipline, while maintaining his aggressiveness in swinging at hittable pitches. He also lost weight in an effort to improve his flexibility. Gyorko agreed to a $510,900 salary for the 2014 season. On April 14, Gyorko signed a five-year extension with the Padres worth $35 million, which was the third largest for a player with only one year of service in the majors. After committing four errors in his first 25 games, Gyorko increased his infield practice with Glenn Hoffman, the Padres’ third base and infield coach.

On December 8, 2015, the Padres traded Gyorko to the St. Louis Cardinals in exchange for Jon Jay, while also agreeing to pay $7.5 million towards the remaining $33 million guaranteed by Gyorko’s contract. The Cardinals intended to use Gyorko as a backup for second baseman Kolten Wong, third baseman Matt Carpenter, and shortstop Jhonny Peralta. He opened the season as the Cardinals’ starting shortstop due to an injury to Peralta. While playing the Pittsburgh Pirates on April 5, he hit his first home run for the Cardinals. Due to the emergence of Aledmys Díaz at shortstop and Wong’s struggles, Gyorko received most of his playing time at second base.

In his first five games against the Padres, Gyorko homered in each game, totaling six, and also had 13 hits in 21 at bats with 10 RBIs. He reached 30 home runs for the first time on October 1, 2016, against the Pittsburgh Pirates, also a game-winning hit.

In 2017, the Cardinals shifted Carpenter to first base, with Peralta and Gyorko playing third base. Gyorko became the Cardinals’ regular third baseman after the Cardinals designated Peralta. Gyorko hit 13 home runs in the first half of the season, but only six after the All-Star break. He finished the year batting .272 with twenty home runs and 67 RBIs in 125 games. Despite two stints on the disabled list in 2018, Gyorko still appeared in 125 games, hitting .262 with 11 home runs and 47 RBIs.

Gyorko returned to a utility role in 2019 after the Cardinals acquired Paul Goldschmidt. He played in 38 games for the Cardinals in 2019, batting .194 with two home runs and seven RBIs, before going on the injured list with a strained back. His rehabilitation was complicated by calf and wrist injuries.

On July 31, 2019, the Cardinals traded Gyorko to the Los Angeles Dodgers along with international signing bonus space and cash considerations in exchange for Tony Cingrani and minor leaguer Jeffry Abreu. He began a rehabilitation assignment with the Tulsa Drillers of the Texas League on August 3. Gyorko debuted with the Dodgers on August 18 against the Atlanta Braves, playing first base and going two for four at the plate. He appeared in 24 games for the Dodgers, with five hits in 36 at-bats (.139). In 2019, he had the slowest sprint speed of all major league third basemen, at 23.8 feet/second. The Dodgers declined Gyorko’s contract option following the 2019 season, making him a free agent.

On January 10, 2020, Gyorko signed a contract with the Milwaukee Brewers, with a club option for 2021. His option was declined after the season, making him a free agent.