Coach Tom Coughlin said that putting Carter on injured reserve is "probably the thing that we'll have to do."
Carter was injured midway through the second period, when he dove for a Kurt Warner pass in the end zone and became entangled with defensive back Tony Dixon.
"He laid out for the ball and just as the ball arrived, so did the defender," Coughlin said. "They went sprawling."
Carter left the field, had X-rays taken and spent the second half watching on television in the Giants' locker room, a pair of crutches by his side.
"We're very, very disappointed," Coughlin said. "Here's a young man that has done nothing but made progress. His game has definitely been improved. Now he's suffering this season-ending injury, which is a hard thing to deal with right now. He did so many different things. He gave us so many different opportunities to press the coverage. We feel very badly for Tim. I know he's real disappointed with having to end the season like this."
Carter has 12 receptions for 182 yards and a touchdown, a 38-yarder against Washington on September 19.
This is the third season in a row Carter has been plagued by injuries. As a rookie in 2002, he suffered a torn Achilles' tendon at Minnesota and played in just five games. Last year, he missed four games and again went on injured reserve because of concussions.
Carter would be the third significant contributor to go on injured reserve since the season began; safeties Omar Stoutmire and Shaun Williams suffered season-ending knee injuries.
Rookie Jamaar Taylor, who has been inactive for each of the first five games, will likely be asked to take Carter's place as the team's deep threat. He had a pulled hamstring early in the season, but has since recovered.
Carter done for year
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