JACKSONVILLE, Fla. — Jaguars cornerback Rashean Mathis will miss the rest of the season after injuring his right knee.

Mathis, who leads the team with four interceptions, sprained the medial collateral ligament in his knee Monday night at Houston and will likely go on injured reserve.

"It's not going to require surgery, but they need to let it heal properly," coach Jack Del Rio said on Wednesday. "He'll be immobilized for a couple of weeks, and by the time they get him going again, we're going to run out of time. So he'll not be available the rest of the season."

With Mathis out, veteran Drayton Florence will move back into the starting lineup.

Mathis, a Pro Bowl selection in 2006 and the first alternate last year, has 33 tackles and one sack this season. He holds the franchise record with 25 career interceptions.

"Obviously, Rashean's a fine football player, one of our top players," Del Rio said. "We'll miss him."

Florence, one of the team's top offseason acquisitions, started the first four games but struggled in zone coverage schemes.

The Jaguars moved Brian Williams back to cornerback, inserted Gerald Sensabaugh at safety and relegated Florence to nickel and dime situations.