On August 10, 2012 LSU Coach Les Miles announced that Mathieu would be dismissed from the football team due to a violation of team rules. Mathieu nevertheless re-enrolled at LSU for the fall semester rather than transferring to another college.
Tyrann Mathieu was named the Cardinals Ed Block Courage Award Winner in 2014 following his return from the knee injury.
Tyrann Mathieu was named NFL Defensive Rookie of the Month for October 2013 after he totaled 21 tackles, two tackles for loss, a sack, an INT and five passes defensed, and was a finalist for AP Defensive Rookie of the Year.
In Arizona, Tyrann Mathieu plays on a defensive unit that features former LSU teammates CB Patrick Peterson and LB Kevin Minter.
In two seasons at LSU, Tyrann Mathieu recorded eight fumble recoveries (two returned for TDs), 11 forced fumbles, four INTs, 16 tackles for loss, 16 passes defensed and six sacks, while also returning 27 punts for 421 yards (15.6 avg.) and two TDs. He was a Heisman Trophy finalist, recipient of the Bednarik Award as the nation's top defensive player and unanimous first-team All-American as a sophomore.
Tyrann Mathieu returned after a season-ending knee injury late in the 2013 campaign to play in 13 games (six starts) last season. He recorded 39 tackles, an INT, five passes defensed and a fumble recovery.
Tyrann Mathieu started 11 of 13 games played as a rookie in 2013 and recorded 63 tackles, a sack, two INTs, 15 passes defensed, four tackles for loss, a forced fumble and a special teams tackle.
Tyrann Mathieu earned first-team All-Pro honors from ProFootballFocus.com as a slot cornerback and was named to the All-Rookie team by the Professional Football Writers of America (PFWA) in 2013.