JACKSONVILLE, Fla. (AP) — Sen'Derrick Marks will follow his best season with his most challenging offseason.

The Jacksonville Jaguars defensive tackle tore the anterior cruciate ligament in his right knee during Sunday's season finale at Houston.

The team's best defensive player twisted his knee on Alfred Blue's 1-yard touchdown run in the second quarter and had to be helped to the sideline. He was on crutches Monday, after tests revealed the extent of the damage.

"I knew as soon as it happened it was something bad," Marks said as teammates cleaned out lockers around him. "I didn't think that it was the ACL."

Marks will have surgery after the swelling subsides.

"My mindset is just to make sure I come back stronger," he said. "I'm not going to let it get me down. I'm going to continue to work and stay positive about it."

Marks will miss the entire offseason, but expects to be back in time for training camp.

Several teammates, including rookie cornerback Aaron Colvin and veteran defensive end Chris Clemons, returned about eight months after similar knee injuries. Both told Marks the injury would benefit him in the long run.

"You've heard of guys coming back playing stronger so I'm going to stay positive about it, hopefully have the surgery soon and just continue to work," he said. "I feel confident. I'm going to keep my mind that way. I'm not going to let it get me down. I'm going to continue to think that way and stay positive about it."

Marks finished with 44 tackles, 16 quarterback hurries and a career-high and team-leading 8½ sacks. His sack total ranked second in the league for interior linemen, an impressive stat considering the Jaguars (3-13) rarely played with the lead.

His last sack, which came on the final play against Tennessee on Dec. 18, triggered a $600,000 bonus in his contract. Marks signed a four-year extension worth $22 million last December. It included $8 million guaranteed, and the Jaguars consider him a cornerstone in their rebuilding process.

Marks was selected as an alternate for the Pro Bowl last week and he had been hoping for a trip to Glendale, Arizona, next month. Instead, he likely will be rehabbing after surgery.

"You hate to see that happen," Jaguars linebacker Paul Posluszny said. "The last game of the year, we're not fighting (for anything). He's going to fight back and rehab. Hopefully we'll have him at some point early next season. But you hate to see that because he had such a great year, he's playing so well. You just want to see him get out of the year healthy. That's a tough deal for him."

But not the kind of setback significant knee injuries used to be.

"We couldn't ask him to do any more," receiver Cecil Shorts III said. "I'm very happy for him when it comes to the season, but disappointed it had to end this way. He's a beast out there. I'm sure he'll get healthy. He's a hard worker and he'll come back better than ever."

___

AP NFL website: www.pro32.ap.org and www.twitter.com/AP_NFL