Indianapolis, IN (Sports Network) - The Indianapolis Colts placed defensive back Marlin Jackson on injured reserve after he suffered a season-ending knee injury in practice earlier this week, and safety Bob Sanders will reportedly miss the remainder of season with a torn biceps tendon.

Jackson suffered the left knee injury during a non-contact drill on Wednesday. It marks the second year in a row that he has torn an ACL.

According to the Indianapolis Star, Sanders will require surgery on his left elbow. ESPN reports that Sanders suffered a torn biceps tendon and will be out for the remainder of the season.

The team released a statement saying Sanders visited with renowned surgeon Dr. James Andrews to gather more information about his injury, suffered last week against San Francisco.

Sanders has played in just two games this year, recording three tackles and one interception. The oft-injured safety has yet to play in a full 16-game season in any of his six years in the NFL.

Additionally, wide receiver Anthony Gonzalez underwent arthroscopic surgery on his injured right knee to clean out loose particles. He suffered the setback during Thursday's practice, and a timetable for his return has not been determined.

To take Jackson's spot on the roster, the team signed defensive end Josh Thomas. Thomas spent 2004-08 with the Colts, starting in 12 of his 68 appearances and totaling 172 tackles and six sacks.