Harry Maguire's late goal spared Manchester United's blushes as they drew 3-3 with Porto despite Bruno Fernandes' red card in the Europa League.
Samu Omorodion's double looked like it had secured Porto the win, but Maguire came off the bench to score in the 91st minute.
Galeno tested Andre Onana with a powerful first-time shot two minutes in, but Marcus Rashford would open the scoring five minutes later at the other end, cutting inside from the left to drill his low shot under Diogo Costa's leg.
He then set up Rasmus Hojlund for their second in the 20th minute, and Costa again should have done better as the shot went through his hand.
Porto showed their fight soon after, though. Onana sprung brilliantly to keep out Noussair Mazraoui's inadvertent header, but Pepe was alert, stooping to nod home from close range.
Samu got his first in the 34th minute, taking advantage of some slack defending as he leapt high to thump his header over the goalkeeper, and got his second after the break, rifling a powerful shot into the top corner.
It looked like United's hopes of a result were over in the 81st minute as Fernandes received a red card for the second consecutive match. He got his first booking in the first half, receiving his marching orders in the 81st for a high boot in the box.
However, the Red Devils kept pushing for an equaliser, and it came from a corner, with Maguire guiding Christian Eriksen's cross into the top-left corner.
Data Debrief: Ten Hag gets lucky
It was a game that summed up United's season in some ways. They started the game on the front foot, getting two quickfire goals to put themselves in control only to drop their concentration.
Since Erik ten Hag joined the club in 2022, no Premier League club has conceded three or more goals in a match more times in all competitions than United (24).
In fact, they are winless in their last five matches in European competition (D3 L2) despite leading by 2+ goals in three of them.
Fernandes' red card against Tottenham may have been overturned, but this one will stand. Having not received a single red card in any of his first 241 appearances for United in all competitions, he has now received two in his last two.