He has previously played in MLB for the San Diego Padres, Seattle Mariners, Baltimore Orioles, and Kansas City Royals.

In 2012, his sophomore year, Frazier set a Mississippi State record for assists in a season (227) and was named the most valuable player of the Southeastern Conference (SEC) Baseball Tournament, and was chosen for the United States national collegiate baseball team.

In 2014, he played for the Bradenton Marauders of the High–A Florida State League, finishing the season with a .252 batting average, one home run, and 42 RBIs in 121 games.

In 2017, Frazier's first full season in Pittsburgh, he batted .276 with six home runs and 53 RBIs over 121 games.

On July 25, 2021, the Pirates traded Frazier to the San Diego Padres, along with $1.4 million in cash, in exchange for infielder Tucupita Marcano, pitcher Michell Miliano, and outfielder Jack Suwinski.

[22] On November 27, 2021, the Padres traded Frazier to the Seattle Mariners for Ray Kerr and outfielder Corey Rosier.

He had five hits with one double, three runs scored, one RBI and one walk in five games with the Mariners in his postseason debut.

He also appeared twice during the American League Division Series against the Texas Rangers, failing to get a hit across five at-bats as the Orioles were eventually eliminated.

On January 30, 2024, Frazier signed a one-year, $4.5 million contract with a mutual option for the 2025 season with the Kansas City Royals.

On October 31, the Royals declined their side of the mutual option, making him a free agent.