Raised by a single father in Tampa, Florida, Joyce frequently attended Rays games at Tropicana Field as a child.

The Detroit Tigers attended an exhibition game that Joyce played with Florida Southern College and selected him in the 12th round of the 2005 MLB Draft.

After stints with the Pittsburgh Pirates, Oakland Athletics, and Atlanta Braves, as well as minor-league appearances for the Cleveland Indians and San Francisco Giants, Joyce signed a one-year deal with the Miami Marlins in 2020.

[2] When Matt Jr. and his sister Danielle were youngsters, their mother, Vallie, who was dealing with substance abuse problems, left the children's father and took the rest of the family to New Jersey.

[4] A childhood fan of the Tampa Bay Devil Rays of Major League Baseball (MLB), Joyce frequently attended home games at Tropicana Field.

As a sophomore in 2005, Joyce earned All-Sunshine State Conference honors and helped lead Florida Southern to their ninth NCAA Division II title.

There, he lived at a dormitory at Hartwick College, in the same hall as Burke Badenhop and Will Rhymes, all of whom would remain teammates as they moved through the Tigers' farm system.

Commenting on the two, Tigers general manager Dave Dombrowski remarked that, "We think they're both prospects... We're not counting on them for this year, but they've got a chance to play at the Triple-A level (this season), depending on how they do this spring.

[24] Although Joyce missed time in spring training due to tendinitis in his leg, he was named to the Rays' Opening Day roster after B. J. Upton sustained a shoulder injury.

[26][27] On April 9, Joyce hit his first major league home run, a solo shot off of Daisuke Matsuzaka in the second inning of a 4–3 victory over the Boston Red Sox.

On the final day of the regular season, a three-run home run from Joyce helped the Rays clinch a Wild Card berth, leading to a series against the Yankees.

[52] Joyce had another productive season in 2014, hitting .254 with nine home runs, but a projected raise to $5 million and steep outfield competition from Jennings, Myers, DeJesus, and Kevin Kiermaier, made the Rays seek to trade him at the conclusion of the year.

He told the Los Angeles Times that he assumed the Monday game was at night and not in the early afternoon, and he worried that the mistake would cause friction with manager Mike Scioscia.

[57] Troubles continued to follow Joyce, who sustained a concussion after colliding with shortstop Erick Aybar in the fourth inning of a 13–7 victory over the Texas Rangers on July 26.

In addition to setting an all-time single-season MLB record for pinch-hit walks with 21 in 81 plate appearances, Joyce led all pinch hitters that season in RBIs with 15 and tied for first with four home runs.

[1] Most egregiously, on May 28, Joyce committed an error that allowed the New York Yankees to load the bases, paving the way for slugger Aaron Judge's first career grand slam.

[70] On August 5, 2017, Joyce received a two-game suspension without pay after using a homophobic slur against a fan in the eighth inning of a game against the Angels.

He additionally clarified in a statement that the outburst had been motivated by a fan saying "vulgar and obscene words" about Joyce and his family, and that he "fully support[s] and hope[s] to help the LGBTQ community with their efforts in being treated fairly.

[74] His recovery process was repeatedly set back; Joyce did not begin rehab assignments until late August,[75] and he was reactivated on September 1 when MLB rosters expanded.

[80] Joyce served primarily as a pinch hitter for the team until August 13, when right fielder Nick Markakis suffered a broken wrist.

[82] Joyce contracted COVID-19 shortly before the Marlins' second summer training camp begun, and, although he was cleared for play prior to Opening Day, he was assigned to the team's alternate site to prepare for live pitching.

The Marlins were forced to temporarily pause their 2020 season due to an outbreak of COVID-19 within the team, and when they returned to play, Joyce had been added to the active roster.

[83] Playing in 37 of the 60 games in the pandemic-shortened 2020 MLB season, Joyce recorded a .252 average, with 32 hits, 14 RBIs, and two home runs in 127 plate appearances.

[22] On October 2, Joyce threw out Willson Contreras of the Chicago Cubs in the fourth inning of the final game of the 2020 National League Wild Card Series.

In the seventh inning, Joyce hit a double, and his pinch runner Lewis Brinson scored off of an RBI single from Magneuris Sierra.

[87] On June 1, Joyce hit a grand slam against Cincinnati Reds infielder Alex Blandino, who had stepped in to pitch, taking the Phillies to a 17–3 lead.

[92] Joyce finished his career with a lifetime .242 batting average in 1,400 games across 14 major league seasons, recording 149 home runs, 898 hits, and 503 RBI in the process.

As his batting improved over the course of his major league career, Joyce told MLB.com that he would watch YouTube videos of performances from Barry Bonds, Ken Griffey Jr., Jose Bautista, and Robinson Cano to understand what made each player successful behind the plate.

During a decline in his productivity at Anaheim, Scioscia, the manager at the time, encouraged Joyce to think of "a concept like driving the ball up the middle or to left center" rather than focusing on physical mechanics of batting.

[96] In December 2018, Joyce and his wife, Brittany, alongside business partner Blair Johnson, purchased the rights to five F45 Training fitness franchises, the first of which opened in New Tampa in May 2020.