Stroud hurt his ankle Sunday when teammate John Henderson fell on him during the first play of the third quarter against Carolina. Stroud sustained a deep bone bruise, a similar injury that hobbled him late last season. He eventually had offseason microfracture surgery.

Stroud acknowledged he took supplements to help recover from the operation and later tested positive for a banned substance. The NFL suspended him for four games. He returned Sunday against the Panthers.

Coach Jack Del Rio said Stroud will be sidelined at least six weeks, too long for the Jaguars (9-4) to consider keeping him on the active roster.

"It's a shame to lose him, but that's the situation," Del Rio said. "Like we've done all year when we lose people, we'll do the best we can to have other people step up, step in and play well, and we expect to continue to play good football."

The Jaguars signed former Houston Texans linebacker Shantee Orr to fill Stroud's roster spot.

Jacksonville already is playing without two defensive starters: linebacker Mike Peterson (hand) and defensive end Reggie Hayward (groin). Both have been ruled out of Sunday's game at Pittsburgh.

Without Stroud, backup Rob Meier will move back into the starting lineup alongside Henderson, and veteran Grady Jackson and rookie Derek Landri will get more playing time.