The Facts: Thomas suffered a serious ankle sprain Sunday that is expected to sideline him indefinitely, a league source told ESPN NFL Insider Adam Schefter.

Diehards Line:He injured his left ankle in the third quarter of Sunday's loss to the Carolina Panthers and didn't return. His injury may provide an opportunity for rookie running back Mike Gillislee to get backup reps behind starter Lamar Miller next Sunday against the New York Jets. Thomas, 26, has rushed for 279 yards on 77 carries with three touchdowns this season. He also has 12 receptions for 54 yards and a touchdown.