INDIANAPOLIS - Indianapolis is keeping Robert Mathis around through 2016.

The team announced Tuesday it had given the 2013 NFL sacks a one-year contract extension. Financial terms were not immediately available.

Mathis is the Colts career leader in sacks and set a single-season franchise record with 19 1/2 sacks last season. But this season has been a washout.

He was suspended for the first four games after violating the NFL's the league's performance-enhancing substance policy, then sustained a season-ending torn Achilles' tendon during a private workout while he was away from the team. Indy (2-2) put Mathis on the reserve/non-football injury list Monday.

The Colts also signed free agent cornerback Jalil Brown and added receiver Chandler Jones and linebacker Rob Ruggiero to the practice squad.