Following the play, the medical staff was looking at his right knee after he walked off the field on his own.
The Steelers, who are passing with ease against the 49ers defense, scored on the next play to take a 22-3 lead.
McDonald is questionable to return to the game.
Vance McDonald injured on punt coverage. Leg injury.
— Cam Inman (@CamInman) September 20, 2015
Vance McDonald is down near midfield. The #49ers medical staff is looking at his right leg.
— Matt Maiocco (@MaioccoCSN) September 20, 2015
Vance McDonald (knee) is questionable to return.
— Matt Maiocco (@MaioccoCSN) September 20, 2015
