Anthony Martial, who had equalised for United, cleared a header from Lamine Kone off the goal line but the ball ricocheted off De Gea's back and went into the net in the 82nd minute.

Wahbi Khazri put Sunderland ahead in the third minute when his curling free kick eluded everyone in the penalty area and bounced into the net. Martial made it 1-1 with a close-range finish in the 39th.

United's first ever loss at the Stadium of Light piles the pressure on its manager Louis van Gaal, whose team is fifth — six points off the top four.