Harris, who leads the Jets with 52 tackles, didn't practice all week after leaving in the second quarter of the Jets' 28-24 victory over Kansas City on Sunday. As he had the previous two days, Harris rode a stationary bike during the time the media are allowed to watch.

Veteran David Bowens would likely start in Harris' place if the second-year linebacker can't play.

Starting safety Eric Smith, who had two concussions in three weeks and was pulled late in the first half Sunday after taking a glancing blow, will not play against the Bills after not practicing all week.

Coach Eric Mangini said earlier in the week that Smith did not suffer another concussion, but the team took him out against Kansas City for precautionary reasons. James Ihedigbo, signed from the practice squad Wednesday, could see some time at safety with starter Kerry Rhodes and Abram Elam, along with cornerbacks David Barrett and Hank Poteat.

Tight end Bubba Franks (hip) didn't practice all week and was listed as doubtful, while linebacker Cody Spencer (shoulder) and tight end Chris Baker (hip) were questionable. Wide receivers Laveranues Coles (thigh) and Jerricho Cotchery (shoulder) were limited for the third straight day, but are probable.