FOXBOROUGH -- They have done everything that’s been asked of them, and it still may not be enough.

Players like wide receiver Terrence Nunn and running back BenJarvus Green-Ellis have played well throughout training camp. They have shown coachability, desire and no small measure of talent. And when called upon in game action throughout the first three games of the preseason, they have played well.

Through three preseason games, Nunn has five catches for 69 yards (better numbers than some players who will make the team, like Wes Welker) as well as three kick returns for 39 yards. Green-Ellis has been the most consistent presence in the backfield for the Patriots in the preseason with 20 carries for 124 yards -- more than twice as many rushing yards as anyone else on the roster.

But with cutdown day looming Saturday (each team must get to 53 players by 4 o’clock that afternoon) every player who might be on the roster bubble knows the cold reality of the situation. Despite their strong training camp and preseason performances, they easily could be cut if New England wants to get a little deeper at another position. Everything they’ve accomplished in a Patriots uniform might not be enough to save them from being released.

That’s why, for many of those players, there’s a real sense of urgency surrounding Thursday night’s preseason finale against the Giants. While the third preseason game is a chance to see if the veterans are in game shape and to get timing down, the fourth preseason game is often a last-ditch chance for someone who might be on the bubble to solidify a spot on the 53-man roster or the practice squad.

“I would expect that the players that played more against Washington will probably play a little less against the Giants,” said Patriots coach Bill Belichick, “and some of the players that didn’t play as much against Washington will play more against the Giants.”

Green-Ellis knows that a strong preseason -- even if you’re perceived as being on the bubble -- can turn the coaches’ heads. He parlayed a stellar 2008 exhibition slate into a spot on the practice squad. In October of last year, he was signed to the active roster after Laurence Maroney went down, and ended up starting three games and rushing for 275 yards in 74 attempts.

Of course, there are stories of backups who have submitted poor preseason efforts and played their way right out of town -- Kevin O’Connell may have done just that this week. After starting training camp as the No. 2 quarterback, he posted three games where he finished 12-for-26 for 108 yards, two interceptions and a quarterback rating of 25.8. He was released on Monday.

“Yeah, it registers,” Nunn said, when asked if he understood the potential ramifications associated with a poor performance Thursday night. “Of course I think about it. I’ve been thinking about that day for a while. But you can’t let it bother you. You’ve just gotta go.

“You know [cutdown] day is coming, so you just have to be prepared for it.”

It’s not only an anxious time for younger players. The last few seasons, there have been a lot of new veterans who were questions marks in training camp. Some have worked out over the course of the preseason, like Sammy Morris. Others, like John Lynch and Victor Hobson, have not.

New veterans like Paris Lenon hope to be closer to the former than the latter. The ex-Lions linebacker did not dress for the first two games, and has appeared to struggle at times to pick up the Patriots’ system -- he said Tuesday the New England defensive scheme is “vastly different from anything I’ve ever done.” 

While his situation may not be as tenuous as the one facing Green-Ellis or Nunn, it’s believed that a strong performance from Lenon is needed Thursday night if he wants to solidify a spot come cutdown day.

“It’s important -- I think anytime you step on the field, it’s important, because you have an opportunity to improve on your craft,” said Lenon when asked about Thursday night. “I’m looking forward to this one.”