The Patriots placed Carter on season-ending injured reserve Tuesday, two days after the team's sack leader suffered a quadriceps injury and was carted off the field late in a 41-23 victory over the Denver Broncos. The Boston Globe had reported Sunday night that Carter's injury would require surgery and likely was season-ending.
The Patriots initially announced Carter had suffered a left knee injury.
"God is great," Carter wrote Monday night on Twitter. "Thank you for showing me and my family support this season. It's been a blast. Wouldn't change it for anything."
Carter, 32, had been a pleasant surprise since joining the Patriots this season, leading the team with 10 sacks while starting all 14 games.
"Andre puts so much in with his leadership alone," Patriots defensive tackle Vince Wilfork said Monday. "He hasn't really won a lot in his career (five years each with the San Francisco 49ers and Washington Redskins), but now he's winning, he's happy here, he's having fun, he's playing well. To see him go down, it's a blow."
The Patriots, who are an AFC-best 11-3 despite allowing the most yards in the NFL this season, switched this year primarily to a 4-3 defense, partly because Carter performs best at defensive end. Without him, New England could revert to the 3-4, especially if Brandon Spikes returns from his knee injury and can line up next to Jerod Mayo at inside linebacker for the AFC East champions.
"I think you can get into a lot of technical aspects of defense and strategy and all that, but we played plenty of four-man line, we played plenty of three-man line," Patriots coach Bill Belichick said Monday. "We used them both at different times for different reasons. In the end, it comes back to the players -- beating blocks, making tackles, hitting the quarterback, covering the receivers."
The Associated Press contributed to this report.