Coach Eric Mangini remained typically tightlipped when discussing the injury, which caused the one-time Pro Bowl linebacker to be removed from the game for a stretch last Sunday at Cincinnati.

"We're still looking at that," Mangini said. "With any injury, we go through the process and evaluate throughout the week."

Rookie David Harris, the Jets' second-round draft pick in April, indicated he will take Vilma's spot in the starting lineup Sunday against the Bills.

"It's a big task for me to fill his shoes," Harris said. "It's been a dream of mine to start an NFL game and the opportunity has arised so I've got to step up to the plate."

Published reports have speculated the injury could be serious and potentially require season-ending surgery. Mangini wouldn't budge when asked if that was a possible scenario.

"It's really just going to matter what the results are and talk to the doctors and put together the best plan," Mangini said.

When pressed on whether that means Vilma could miss the rest of the season, Mangini said simply: "No, it just means that we're looking at the tests and talking to doctors and following the normal procedure that we do with everybody."

Vilma has not been available to the media since Sunday. Messages and e-mails left for Tony Fleming, one of Vilma's representatives, were not immediately answered.

Mangini said he wasn't sure when the injury occurred, but shot down the theory that it might have been a preexisting condition.

"The injury was really based on the game," he said.

Mangini also wouldn't specify whether the injury was to Vilma's right or left knee.

"It's one of those two," he said.

The Jets coach then explained why he doesn't want to say which knee it is.

"Just historically, whenever you have an awareness of an injury and opponents have an awareness of an injury that's something that you can take into account when you're running routes, when you're running plays, the directions that you run plays, how a guy can cut or not cut, where they're going to be quicker," he said. "What may be affected, that does come into the decision-making. What kind of routes you're going to run against them. What the likelihood of being able to take advantage of a slowed-down player might be."

The hard-hitting Harris, who has 24 tackles in limited time this season, could get the chance to call signals at middle linebacker Sunday.