NASHVILLE, Tenn. -- With a new staff in place, plenty of Tennessee Titans have to show what they can do in order to earn a chance to be around long-term.

But before he’s played a regular-season down for the new staff, defensive lineman Jurrell Casey ’s earned a four-year contract extension that his agent says is worth $36 million, with $20.5 million guaranteed.

That comes on top of the final year of Casey’s rookie deal, which calls for a $1.431 million base salary. He was a third-round pick out of USC in 2011.

Casey was a tackle in the team’s 4-3 in his first three seasons and is now an end in the base 3-4, shifting inside on nickel downs.

He brings a great combination of strength and quickness and expects to build on the 10.5 sacks he made a year ago.

The extension shows the Titans are ready and willing to invest in foundational pieces. Casey is a very good player, the best on a defense that seems, though three preseason games, to be lacking firepower.

No other player from the 2011 draft class is a candidate for an extension at this point.

The Titans declined to execute an expensive 2015 option for quarterback Jake Locker, who is playing to prove he’s the guy for beyond this season.