INDIANAPOLIS -- The Indianapolis Colts continue to improve their linebacker group, as they’ve agreed to a three-year deal with former Houston Texans linebacker John Simon. Simon has 120 tackles and 10 sacks in his four-year NFL career. His best season was in 2015, when he had five sacks.

Terms: Three years, $13.5 million

ESPN 150 ranking: No. 59

Grade: B-plus. Simon has started 12 of the 27 games that he’s appeared in over the past two seasons and he’s recorded 8.5 sacks in that span. Simon fits the mold of what new Colts general manager Chris Ballard is looking for as he fixes the roster. Simon is young – 26 years old – he comes from a team that has been successful defensively, and he fills a need on the roster.

What it means: First off, Simon’s signing likely means Erik Walden, who led the Colts in sacks with 11 last season, won’t be re-signed. Simon, according to ESPN Texans reporter Sarah Barshop, is a run-stopping linebacker who sets the edge. That’s the same position Walden plays. Simon spent last season on a Houston defense that gave up the fewest total yards allowed per game (301.3) in the NFL. The Colts need all the help they can get when it comes to stopping the run because they struggled in that area last season. The Colts were 25th against the run, giving up 120.4 yards on the ground.

What’s the risk? Simon has to adjust from being a part-time player in Houston to a full-time player with the Colts. He was behind Whitney Mercilus and Benardrick McKinney on the depth chart on one of the NFL’s best defenses. It also didn’t help that Simon missed five games to chest injuries last season. This is a smart move by the Colts because Simon knows what it takes to play on a successful defense, something that hasn’t happened in Indianapolis under coach Chuck Pagano.