Updated

The Arizona Cardinals signed defensive back Tyrann Mathieu to a four-year contract on Thursday.

Details of the contract were not released, but NFL.com says it's a $3.052 million deal that comes with an initial signing bonus of $265,000. The balance of the $662,500 bonus is spread over years 2-4.

The only way Mathieu doesn't get the full payment is if he's dismissed from the team for drug use.

The former LSU standout was kicked off the school's football team prior to the 2012 season due to drug-related issues, but the Cardinals selected the talented defensive back in the third round of last month's draft.

In two seasons at LSU, Mathieu had eight fumble recoveries, 11 forced fumbles, four interceptions, 133 tackles, 16 passes defensed and six sacks. He also returned 27 punts for 421 yards and two touchdowns.

As a sophomore in 2011, Mathieu started all 13 games and collected 76 tackles, 1 1/2 sacks and two interceptions. He was a Heisman Trophy finalist, recipient of the Bednarik Award as the nation's top defensive player and unanimous first-team All-American.

The 21-year-old Mathieu becomes the sixth member of Arizona's nine-player 2013 draft class to sign.