O'Brien would be the latest ex-head coach to serve as the Crimson Tide's offensive coordinator under Nick Saban, replacing Steve Sarkisian after Sarkisian leaves for Texas following Monday's national championship game. O'Brien would inherit the county's No. 1 offense at the Power 5 level, but the unit is also expected to see stars DeVonta Smith, Najee Harris, Jaylen Waddle, and Mac Jones depart for the NFL.
The 51-year-old has experience at the college level, previously posting a 15-9 record in two seasons as head coach at Penn State before joining the Texans.
O'Brien amassed a 52-48 record in seven seasons with the Texans before the team fired him after an 0-4 start to the 2020 campaign. The 2012 Big Ten Coach of the Year has experience as an offensive coordinator at both the collegiate and NFL levels, previously serving in the role for Georgia Tech, Duke, and the New England Patriots.