Bills starting cornerback Nate Clements missed practice Wednesday because of a sore right quadriceps, and it's uncertain whether he'll play against Detroit this weekend.

Coach Dick Jauron held out hope that Clements will be able to practise by Friday and ready to play Sunday.

Clements was hurt when he was leg-whipped by a Bears player in a 40-7 loss at Chicago last weekend.

Listed as questionable, Clements did not walk with a limp Wednesday, a notable improvement after he had difficulty getting around the locker-room Monday.

If Clements is unable to play, reserve Kiwaukee Thomas would take over as starter against the pass-happy Lions (0-5), depleting what's an already young and inexperienced defensive backfield. Buffalo (2-3) is already starting two rookie safeties: first-round draft pick Donte Whitner and fourth-rounder Ko Simpson.

The Bills defence is further banged up with rookie defensive tackle John McCargo out indefinitely after surgery Monday to repair a left foot broken last weekend.

Jauron described the surgery, in which a screw was inserted into McCargo's foot, as successful, but would not discuss how much time McCargo would miss.

Down to three defensive tackles, the Bills are considering whether to sign an additional tackle to their active roster.

``We're thin,'' general manager Marv Levy said. Levy added he didn't foresee the team playing with three defensive tackles for an extended period and that a decision would be made this week.

The Bills brought in five free agents, some of them defensive tackles, for a workout on Wednesday. The team is also carrying defensive tackle Jason Jefferson on its practice squad.

Linebacker Takeo Spikes, who's missed four straight games with a hamstring injury, practised fully, but is still listed as questionable.

Starting right guard Chris Villarrial (ankle) is questionable after he missed last weekend's game.

© The Canadian Press, 2007