ALLEN PARK — Lions cornerback Bill Bentley has a torn anterior cruciate ligament and will miss the rest of the season. The team announced on Tuesday they placed Bentley on injured reserve.

Bentley, who plays nickel, injured his knee in Monday night’s win over the Giants.

He was helped off the field and did not return to the game.

The Lions had only five cornerbacks on the 53-man roster including Bentley. Rashean Mathis and Darius Slay are the starters with backups Cassius Vaughn and rookie Nevin Lawson.

Vaughn, who didn’t play a defensive snap on Monday, could start with Mathis moving  to nickel.

It’s possible the Lions will either move up their practice squad cornerback Mohammed Seisay or find a free agent. They play at the Carolina Panthers on Sunday.

Safety Don Carey, who didn’t play on Monday with a hamstring injury, is versatile enough to play nickel (and he did so in games last season), but the Lions have only five safeties on the roster. James Ihedigbo, who was expected to start, was inactive on Monday with neck and knee injuries.

The Lions worked out veteran Champ Bailey last Thursday. Bailey is 36 and was let go on the final cut day for the New Orleans Saints after he was cut by the Broncos in early March. He played only five games in 2013 due to a Lisfranc foot injury.

Lawson was thrown into the fire on Monday night, playing 82 percent of the defensive snaps. 

“I think he fared decently,’’ Caldwell said. “It was a challenging situation for him I think he learned a lot and hope he continues to grow.’’

The Lions have not issued a statement regarding Bentley. Jim Caldwell said during his 2:15 p.m. press conference that he would have information later today on Bentley and LaAdrian Waddle (calf strain). The coach also said he might not share the information with the media.

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