Mathieu was hurt with under three minutes to play when he intercepted a pass from Sam Bradford. His left ankle got caught in the turf and he fell awkwardly to the ground.
Mathieu remained on the ground for several moments before heading to the locker room under his own power.
Mathieu, 23, tore the ACL and MCL in his left knee as a rookie in 2013 and missed the final three games of the season. He returned last year to play in 13 games with six starts.
Mathieu leads the team with 76 tackles this season and is second on the team with four interceptions. He has started all of Arizona’s 14 games.
- Dan Gartland