Manchester United are on the brink of an early exit from the Champions League after blowing a 2-0 lead to lose 4-3 on Wednesday to Copenhagen as Marcus Rashford was sent-off in the Danish capital.
Rasmus Hojlund looked to have come back to haunt his former club by scoring twice inside half an hour.
But Rashford's sending-off swung the destiny of the match and possibly sealed United's fate with a third defeat in four games in Group A.
Mohamed Elyounoussi and Diogo Goncalves from the penalty spot levelled for Copenhagen before half time.
Bruno Fernandes' spot-kick briefly put United back in front, but two goals in the final seven minutes from Lukas Lerager and 17-year-old Roony Bardghji handed Copenhagen their first Champions League win since 2016.
United sink to the bottom of the group, one point behind Galatasaray and Copenhagen, with two games left to play.
The Red Devils travel to Galatasaray in three weeks' time before hosting runaway group winners Bayern Munich.
Defeat will again ramp up the pressure on United boss Erik ten Hag as a disastrous start to the season in both the Premier and Champions League goes on.