Manchester United captain Bruno Fernandes was sent off as his side went down 2-0 at Wolverhampton Wanderers on Thursday – a fourth defeat in their last five Premier League games.
Fernandes earned a second yellow card two minutes after the interval and with Boxing Day fog swirling at Molineux, United's gloom deepened as Matheus Cunha scored direct from a corner.
It was an embarrassing moment for United keeper Andre Onana and one that summed up the malaise at the club as they languish in the bottom half of the table.
Wolves held on through a nervy eight added minutes against the 10 men and Hwang Hee-chan made absolutely sure with virtually the last kick after a counter-attack to make it a joyous first home game in charge for new manager Vitor Pereira who began his reign with an away win at Leicester City.
Victory lifted Wolves out of the bottom three into 17th place with 15 points from 18 games while Ruben Amorim's United ended the day in 14th place with 22 points.