The Raiders (1-2) had brought in Carter twice before for workouts in training camp and earlier this season before signing him to fill a glaring need.
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"I think he'll be instrumental," said Raiders defensive tackle Richard Seymour, who was picked one spot ahead of Carter in the 2001 draft at sixth overall. "He's a proven guy in this league. Obviously, it will take some times to get his legs under him, but he's a guy that's shown he can rush the passer, and I think that will be essential for us."
Carter has 76 sacks in 163 career games over 11 seasons in the NFL. He was named to the Pro Bowl for the first time last season after recording 10 sacks for the New England Patriots, but his season was cut short by a quadriceps injury that forced him to miss the final two games of the regular season and the postseason.
But because of the injury, Carter was still looking for a job this season.
"It's always tough," he said. "It definitely gives you a different perspective. Here I am trying to train hard and work hard and just get better, and as the season continued to progressed and watching Sunday football on the couch with my son ... I knew God had a plan, and I just kept on continuing to be patient, and in the end, it worked out well."
Copyright 2012 by The Associated Press