Didier Drogba left the pitch on a stretcher during Chelsea's 3-1 win over Norwich, following a bad landing after he appeared to be knocked-out in a mid-air challenge with the Canaries' keeper.
John Ruddy mis-timed his attempt to punch the ball clear, moments after Norwich netted their equaliser, and instead struck the Ivorian in the head.
Drogba, who had jumped to challenge for the aerial ball, appeared to be unconscious in mid-air before he hit the ground face-first.
The stoppage resulted in 11 minutes of injury time.
Chelsea are yet to provide an update on the striker's current condition.
