Career
He played college football at University of Southern California, and was drafted by the Titans in the third round of the 2011 NFL Draft. Casey played for the University of Southern California Trojans football team while attending the University of Southern California from 2008 to 2010. As a freshman in 2008, he played in 12 games for the Trojans recording 12 tackles and three forced fumbles.
As a sophomore in 2009, Casey became a starter and was All-Pac-10 honorable mention.
Tennessee Titans
Casey was selected with the 77th overall pick in the 2011 NFL Draft by the Tennessee Titans. In his first season, he started 15 games in which he recorded 2.5 sacks, led all Titans defensive linemen with 74 tackles and came second overall in tackles for loss, with 5.
In 2013 Casey recorded a career high 10.5 sacks in 15 games. On August 27, 2014, the Titans signed Casey to a four-year, $36 million contract extension with $20.5 million guaranteed.
After the 2013 season he was selected to the NFL Pro Bowl as an alternate, but he rejected the invitation.
The same happened after the 2014 season but he also declined the invitation.
