He played college football for the Auburn Tigers, and was selected by the Tennessee Titans in the second round of the 2009 NFL draft.

[6] Marks finished his collegiate career with 115 total tackles, 7.5 sacks, one interception, four passes defensed, and one forced fumble.

[12] He made his NFL debut in Week 4 of the 2009 season against the Jacksonville Jaguars and recorded a solo tackle in the 37–17 loss.

[13] In the 2009 regular season finale against the Seattle Seahawks, Marks recorded his first career sack against Matt Hasselbeck.

He started all 16 games and recorded four sacks, 34 total tackles, six tackles-for-loss, ten quarterback hits, eight passes defensed, and two forced fumbles.

He started all 16 games and recorded 8.5 sacks, 44 total tackles, 15 tackles-for-loss, 17 quarterback hits, and three passes defensed.