Josh Heupel coached and played at Oklahoma before he became Tennessee's coach. Here's why he was fired at his alma mater after 2014:

When former Oklahoma player Chris Hammons stood on Tennessee's sideline with Josh Heupel, it shocked Sooners fans. But he had a heartfelt reason.

The Tennessee Volunteers, led by head coach Josh Heupel, secured an emotional victory to kick off SEC play. The Vols traveled to Norman and defeated Heupel's alma mater, the Oklahoma Sooners. Heupel played a pivotal role in winning Oklahoma's last national championship in 2000 as the team's starting quarterback before transitioning to a coaching role at the school.

Tennessee coach Josh Heupel told QB Nico Iamaleava that he 'pulled back a tad' late in a win at Oklahoma because of how well the defense was playing

Tennessee Head Coach Josh Heupel comments on their win over Oklahoma