He spent the next four years playing college basketball at Mercer University (1981–85), and scored nearly 2,000 points, becoming the leading scorer in Bears history.

Mitchell had enlisted in the Army during his junior year, and at the conclusion of the 1985 NCAA tournament he went to boot camp at Fort Bragg, North Carolina.

Unhappy in the CBA, Mitchell quit the team midway through the season to return home to Georgia, where a former professor hired him a special education teacher for the remainder of the school year.

He rejoined the Rockets for training camp afterwards, but was once again cut and joined the CBA, splitting the season between the Wisconsin Flyers and Rapid City Thrillers.

He then joined the French LNB Pro A team of Montpellier Basket (coached by Pierre Galle) for the end of the 1987–88 and the whole 1988–89 season.

Success overseas led to a renewed interest from the NBA, and Mitchell earned a contract with the newly-formed Minnesota Timberwolves.

Mitchell was named the coach of the month in January 2007 for his effort bringing the Toronto Raptors back to .500 and leading the Atlantic Division.

On March 30, 2007, Mitchell got his 100th win as NBA coach when the Raptors defeated the Washington Wizards at the Verizon Center.

On December 3, 2008, after leading the Raptors to a disappointing 8–9 start to the 2008–09 season, Mitchell was relieved of his duties as the team's head coach.

On 2012, Sam Mitchell named head coach of USA select to 2012 William Jones Cup in Taiwan and his team finished bronze medal.

[7] On September 11, 2015, Mitchell became the Timberwolves' interim head coach after Flip Saunders had to take a leave of absence to receive treatment after being diagnosed with Hodgkin lymphoma.