Romelu Lukaku left the Old Trafford pitch on a stretcher after a nasty clash of heads in the first half of Manchester United's game against Southampton.
The Belgium striker went up to contest an aerial ball with Saints defender Wesley Hoedt and came off second best as the pair inadvertently clashed.
A handful of United medical staff arrived on the pitch to assess and treat Lukaku, who had missed a glorious chance to open the scoring in the third minute, and the delay lasted for more than five minutes.
Eventually he was carried from the field with an oxygen mask attached to his face as manager Jose Mourinho looked on with concern.
The entire crowd, home and away fans, gave the striker an ovation and England striker Marcus Rashford was sent on as his replacement.