Kansas City Chiefs running back Jamaal Charles—who played in just five games last year after he tore his ACL—was placed on injured reserve Tuesday with a knee issue, per Adam Schefter of ESPN.
Ed Werder of ESPN noted the Chiefs couldn't determine where Charles' knee pain emanated from, while "Dr. James Andrews was having similar difficulty."
Charles has played in just three games this season.
Ian Rapoport of NFL Network and NFL.com said the severity of the injury isn't clear but noted Charles will need another surgery on the knee after he visited with Andrews.