United travelled to Spain for the first leg against Granada and, as is usual at the moment, were expecting not to see any fans in the ground.
During the first half though both sides got to see far more of an audience than they might have wanted, even though it was only one person.
A bearded, and very naked, man appeared during the match and ran across the pitch, before four policemen managed to chase him down.
It's now been reported that the streaker had snuck into the ground at 7 am local time on Thursday and had waited 14 hours before appearing during the match.
The man is reported to have been Olmo Garcia, a local Granadan man, who is well known to local authorities because of his nudist ways.
The stunt was reportedly in order to raise awareness for "human and environmental sustainability," although it probably just raised awareness for the match.
Speaking a few years ago about his nudist ways, Garcia said, "For me it is a way to claim purity, peace, to show that when you take off your clothes you are more sincere with everything that surrounds you.
"I do not think it is wrong in the head to go naked according to a philosophy or ideals. I do not bother anyone and I think this is good for society," he might have bothered one or two people on Thursday.
The game was just minutes old when it was interrupted and neither side had broken the deadlock, and it would take the players another 25 minutes to do so, possibly trying to get over the incident.
When the goal did come it was well worth waiting for as Victor Lindelof's perfect ball over the top of the Granada defence found Marcus Rashford's run and the forward took an excellent touch before slotting home.
United dominated possession but failed to open the hosts up a second time, as the full time whistle approached, before Bruno Fernandes was pushed in the penalty box late on.
The Portugal midfielder got up to score the spot kick, just about, and put the English side in a great position to advance into the semi-finals.
United and Granada will hope the next time there's fans in the stadium it won't be such a close view!
Featured Image Credit: BT Sport/PA
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