Chicago Bears outside linebacker Khalil Mack will miss the rest of the season due to a foot injury requiring surgery next week.

The 30-year-old six-time Pro Bowler sustained the injury in the Bears' Week 3 defeat to the Cleveland Browns but played on for the next four games.

Mack had missed the Bears' past two games – defeats to the San Francisco 49ers and the Pittsburgh Steelers – and head coach Matt Nagy confirmed he will require season-ending surgery.

"With him, it's been the last several weeks just trying to get right," Nagy told reporters.

"I think we did everything as far as trying to attack it the right way with him, and I know he's put a lot of time and energy in trying to get back and see where things are at. But this is where we're at.

"I know he's frustrated because he's such a competitor. But this is the best thing for him and the best situation to be able to help him out and get it fixed."

Mack joins veteran linebacker Danny Trevathan on injured reserve for the Bears who have a 3-6 record and face the Baltimore Ravens on Sunday.

Former NFL Defensive Player of the Year Mack recorded 19 tackles, 6.0 sacks and six tackles-for-loss across seven games this season.