He played in MLB for the Tampa Bay Devil Rays, Anaheim Angels, and Texas Rangers and in the KBO League for the Hyundai Unicorns.

On May 26, 2021, following an investigation into allegations of sexual harassment spanning much of his career as a manager and coach, Callaway was banned from Major League Baseball through at least the end of the 2022 season.

The Tampa Bay Devil Rays selected Callaway in the seventh round of the 1996 Major League Baseball draft.

He was released by the Angels and then subsequently signed by the Texas Rangers at the end of 2003, and finished his Major League career with them in 2004.

After being sidelined by an elbow injury in 2007, Callaway served as the interim Head Coach of Texas A&M International University[5] in 2008.

In the 2008–2009 off-season, he signed with the Uni-President 7-Eleven Lions of the Chinese Professional Baseball League, and won his final start to clinch a play-off berth for the team.

[12] He was suspended pending an investigation into sexual harassment allegations dating to his time as a coach in Cleveland,[13] and fired soon after MLB banned him from the game for at least two years.

[19] On October 6, 2021, Callaway was hired by the Acereros de Monclova to manage their winter league developmental team.

[20] In the league's inaugural season, he led the team to a championship, defeating the Pericos de Puebla in the Serie del Príncipe.

[24] In early 2023, Callaway was announced as the team's pitching coach,[25] but was not on the Opening Day roster and later cut ties with the organization.

On February 1, 2021, The Athletic released an article that detailed allegations of five women against Callaway's "lewd behavior", including sending inappropriate photographs.

[28] On May 26, 2021, Commissioner Rob Manfred announced that his office's investigation concluded that Callaway had violated MLB policies on harassment.