However, after Antony had hit the crossbar, Sevilla came back into the contest and profited from a terrible ending to the game for Erik ten Hag's men.

First Tyrell Malacia diverted the ball past David de Gea after former Manchester City man Jesus Navas had pulled a low cross back from the goalline.

Then, two minutes into injury time, Youssef En-Nesyri's off-target header struck Harry Maguire to leave De Gea helpless as it flew into the net.

The scoreline is bad enough as it leaves United facing a battle to secure the semi-final spot they seemed to have virtually sealed.

However, the loss of Martinez is a major concern, particularly as Raphael Varane had to be replaced at half-time.

Martinez had to be carried from the field by his Argentina team-mates Gonzalo Montiel and Marcos Acuna and then left for the dressing room on a stretcher in obvious pain after catching his foot in the turf with no opponent near him.

Martinez injury fear

Lisando Martinez's Argentina team-mates Marcos Acuna and Gonzalo Montiel helped to carry him off

Having opted against replacing Marcus Rashford when his side were two goals up against Everton at the weekend and seeing the England man get injured, it was probably not a surprise when United boss Erik ten Hag took off key man Bruno Fernandes, plus Jadon Sancho and Anthony Martial after an hour.

At that point United had a healthy advantage, with Sabitzer profiting from excellent through balls from Fernandes and Martial and Ten Hag presumably reasoned it was a wise option not to take a risk with so many big games to come, knowing Fernandes is banned for the second leg anyway after he picked up another yellow card.

But the decision allowed Sevilla to gain some momentum. United's goal came under threat and eventually, their lead disappeared.

Arguably though, the extent of Martinez's injury is of more concern.

The Argentine has been a rock at the heart of United's defence this season and, given the clear pain he was in as he sat sadly by the touchline waiting to be carried to the dressing rooms, there must be huge uncertainty over when he will play again, which could place his side's season under a threat that previously did not seem to exist.

Martial's time to shine

If there is some comfort to be taken from a night that ended so badly, it came from the performance of Martial.

Ten Hag quoted "stats" in the build-up to the game when he said United were a better team with the Frenchman in it.

The problem is that, since he arrived from Monaco in 2015, United fans have seen the 27-year-old be maddeningly frustrating, capable of brilliance in one moment before disappearing for extended periods - either figuratively in terms of his contribution to the team or literally by being injured.

If ever there was a time for Martial to step up, this is it.

No timescale has been put on Rashford's absence but even if it was just to the end of the month - and the belief is it will be slightly longer - that would take in the rest of this tie, the FA Cup semi-final with Brighton and a crucial league game at Tottenham in the battle to secure a Champions League spot. Martial has to stay fit and he has to perform.

His contribution to Sabitzer's second goal emphasised why.

Collecting the ball inside the Sevilla half, Martial took his time, created some space, then delivered a perfect through ball. Immediately after he scored, Sabitzer pointed to Martial in grateful acknowledgement.

Martial's last involvement was to superbly hold-up possession as United cleared their lines from a Sevilla attack, setting in motion a move that ended with Antony firing against the crossbar.

Ten Hag has praised Wout Weghorst for his contribution but the on-loan Burnley forward is not in the same class.

'Second half complete disaster'

Ten Hag said afterwards he took Antony and Fernandes off to avoid them being red carded after being told the pair were on the last warnings.

The United boss felt his side should have scored "three or four" but also conceded they were unlucky with injuries and the two late own goals.

"We have to learn and have to kill the game but everything is open," he added on BT Sport.

"When we didn't get the third and got some injuries we lost the rhythm in the game. We played well in the first half with a lot of belief, scored two great goals for Sabitzer and we could've scored even more, then after half time we lost control of the game.

"I know we can do better with these players in the last part of the game and we needed to be more composed, it was not a nice night."

Former Manchester United midfielder Paul Scholes, a pundit on BT Sport, called the second half "a complete disaster".

"You never felt Sevilla put loads of pressure on United," he added. "United must have felt this was going to be a stroll in the park."