The Indianapolis Colts have signed veteran free agent DE Josh Thomas and have placed CB Marlin Jackson on injured reserve, the team announced Friday.

WR Anthony Gonzalez underwent arthroscopic right knee surgery yesterday to clean out loose particles, and SS Bob Sanders visited with Dr. James Andrews yesterday to gather additional information on the left elbow injury he suffered last Sunday against San Francisco.

Jackson suffered the left knee injury during a non-contact drill early in Wednesday’s practice. Gonzalez suffered a recent setback in practice that led to yesterday’s procedure. A timetable for his return is not determined.

Jackson's loss shouldn't be much of a factor since he only appeared in four out of seven games this season and he didn't start any of them. Jackson suffered a torn ACL last year and was still dealing with problems throughout the first half of this season. However, had he been healthy, he would have given the team size and physicality to the cornerback position.

Thomas played 2004-08 with the club, starting 12 of 68 appearances. He totaled 172 tackles and six sacks. He had a brief stint with the club this past training camp.

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