Harry Maguire's stoppage-time header rescued a point for Manchester United in Porto as they recovered from a stunning collapse to draw 3-3 in the Europa League despite Bruno Fernandes being sent off for the second game running.

United threw away an early two-goal lead after strikes from Marcus Rashford and Rasmus Hojlund and looked on course to have a nightmare evening when Fernandes, sent off against Tottenham, was given a second booking for a high foot nine minutes from time.

Porto struck twice in the space of seven minutes to go in level at the break as United wilted in Europe once again. Pepe poked in at the back post before Samu Omorodion, who nearly joined Chelsea in the summer, outmuscled Matthijs De Ligt to power in a header.

Rashford, the first-half's best player, was taken off at half-time for "rotation", Ten Hag said afterwards, leaving United blunt in attack, although he later suggested it was because of his defensive frailties.

Porto only needed five minutes after the restart to go ahead, Omorodion besting De Ligt again before scoring emphatically into the roof of the net. United escaped with a point at the death thanks to Maguire who nodded in Christian Eriksen's corner.

United, winless in four games, remain in the knockout play-off spots in 21st after two draws. Porto are also just in the same bracket in 24th after claiming their first point in the new Europa League format.

Ten Hag asked fans for patience once again after the game, telling TNT Sports: "We will get there. Don't judge us in this moment, judge us at the end of the season. We are in the process, we will improve."

United bosses backed Ten Hag after humiliation against Tottenham, but the nature of this performance only adds to the pressure on the manager. A tough trip to Aston Villa awaits on Sunday - live on Sky Sports.

Ten Hag failed to learn his lesson from resting Rashford at Crystal Palace for last month's stalemate just when he was finding form and it cost him in Porto.

Rashford was the star turn for United in the first half, scoring and assisting, so it was a surprise to see him being replaced by Alejandro Garnacho before the restart.

"We have to rotate," Ten Hag told TNT Sports, asked about the decision. "We didn't start Garnacho, but he had a great game not only Sunday but the whole season.

"We go quickly with a turnaround to Villa and they have had a day longer to recover and we have an away game."

Rashford had been the source of United's best attacking moments in the first half and finished with a game-high eight touches in the opposition box despite playing only 45 minutes.

The forward's loss was felt in the second half as Garnacho struggled against Porto right-back Joao Mario, who Rashford seemed to have the beating of.

Going the other way, the 26-year-old was less convincing. It was Joao Mario that delivered the cross for Porto's first goal, Rashford watching on a few yards back. Ten Hag later suggested this might have been behind the change.

Asked if the decision had anything to do with Rashford's role in Porto's first goal, Ten Hag said: "As I say, I have to watch it back and I think over the left side definitely we didn't defend well tonight.

"Marcus also played a part in this but, as I say, it had to do with Garnacho and nothing against Rashy."

For a manager under so much pressure right now, removing your best attacking player with the game level seems a perplexing decision. It appears to have backfired. Villa on Sunday becomes an even bigger game as a result.

The seven-minute collapse that led to Porto overturning the early two-goal deficit felt familiar for United in Europe. It was a common occurrence in last season's disastrous Champions League campaign that ended in them finishing bottom of their group.

Ten Hag's side conceded two goals in four minutes at Bayern Munich and Copenhagen, and then twice within 10 minutes home and away against Galatasaray. A year has passed, with five signings made for more than £200m, but the same chaotic team remains.

Once Pepe scored Porto's first, on the rebound after Andre Onana kept out Noussair Mazraoui's inadvertent header, it only felt a matter of time before the equaliser followed.

These are the concerning characteristics of the team that Ten Hag cannot hide from, regardless of his trophy return or the outcome of the game. This is an unsustainable style of football.

This is a team that never looks safe, even with a two-goal lead.

Ten Hag told TNT Sports after the game: "We started very good, we dominated, scored two goals then we lost control.

"The start was good, the middle was not good then we finished very good. It's a tough place to go, we're coming back from 3-2 and we get the equaliser. The team has a strong character, but the middle part we have to improve.

"We need to be better on the ball, keep switching. We had good players, a good plan. We have to defend better. We had three clean sheets not a long time ago so we can defend very good, but we have to go back to those habits."

He added: "We will get there. Don't judge us in this moment, judge us at the end of the season. We are in the process, we will improve. We have had two seasons where we have reached finals, we will continue and fight.

"You see the spirit and the connection between the staff and the team. The players are together, they have a strong spirit and they want to achieve. We have a good mentality but in some defending parts we have to step up."

Maguire was only on the pitch for his goal, it seemed, because De Ligt and Lisandro Martinez had endured such a torrid evening trying to deal with Omorodion. They were lost.

This was a performance that announced the 20-year-old on the European stage. He now has seven goals in his last five games and Porto appear to have a gem on their hands.

Omorodion was a threat from start to finish and tormented De Ligt, fresh from a difficult display against Spurs, with both his goals coming when up against the Netherlands defender.

Chelsea passed up on the chance to sign Omorodion from Atletico Madrid in the summer after contractual issues held up the transfer. They turned to Joao Felix instead as the player to unlock Conor Gallagher's move to the Spanish capital.

There may be a few wistful onlookers at Stamford Bridge now.