San Francisco 49ers star running back Christian McCaffrey was taken to the locker room during Sunday Night Football in a snowy Orchard Park, New York, against the Buffalo Bills.
McCaffrey was taking a handoff in the cold and wintry conditions early in the second quarter when he appeared to suffer some sort of injury to his leg.
He slipped on the snowy surface of Highmark Stadium and was later piled on by several Bills players.
McCaffrey was able to walk off the field under his own power and then went into the blue tent with the medical staff and then to the locker room.
According to team officials, McCaffrey has suffered a knee injury and is questionable to return.
It is unclear exactly which leg was injured, as two competing theories have since emerged as to when McCaffrey hurt his knee.
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