Manchester United fans were left annoyed at what they considered a 'double standard,' following Erik Lamela's challenge on Casemiro.
Erik ten Hag must be waking up on Friday morning thinking that the end of United's game with Sevilla on Thursday night was all some horrible dream.
Whilst Raphael Varane and Lisandro Martinez both went off injured, the latter with what seemed like a particularly nasty injury, the team threw away a two goal lead.
All had been going well when Marcel Sabitzer produced two fine goals in the first half to continue the side's excellent form in their weird Europa League/Copa del Rey hybrid campaign.
But by the end of the night pretty much everything that could go wrong had somehow gone wrong, with Bruno Fernandes picking up a yellow card that meant he would miss the second leg.
Perhaps the only thing that Ten Hag avoided seeing go belly up was the fact that Casemiro, back in the team for the first time since he picked up a domestic suspension for four games, didn't also pick up a yellow card and get another suspension.
However, the Brazilian was still involved in a contentious moment, with former Tottenham Hotspur star Erik Lamela booked for a challenge on the midfielder.
The Argentine's studs up challenge on the shin of his fellow South American was only worth a yellow card, but many felt that had the boot been on the opposite shin then it would have certainly been a red.
No red card was given after this Lamela challenge on Casemiro. pic.twitter.com/gBxtZdXBc0— ESPN FC (@ESPNFC) April 13, 2023
"If it was the other way around Casemiro would’ve gotten two reds," joked one.
"If it’s the other way around Casemiro is immediately off, embarrassing. Hope Sevilla liquidates," added a second, not in the slightest bit bitter at the Spanish side's comeback.
One conspiracy theorist claimed, "Way worse than Casemiro's slip vs Saints. Absolute banter officiating again. UEFA got what they wanted, what they had planned to happen, didn't they."
"All ya’ll commenting that Lamela got the ball first clearly don’t remember Casemiro’s red card," added a fourth, also referencing the former Real Madrid star's second red of the season.
Another conspiracy theorist posted, "Erik Lamela gets away with a double stamp worse than what Casemiro got a 5 game ban for. European officiating against Spanish opposition never changes."
And on Fernandes' yellow card a sixth fan noted, "So Lamela stamping on Casemiro’s leg and Bruno happening to possess an arm are apparently equal offences."
It wouldn't have helped the mood at Old Trafford that Fernandes picked up his booking just minutes later when he was adjudged to have blocked a long range shot with his arm.
The midfielder's arm wasn't in an unnatural position and he didn't move it towards the ball, but nonetheless the referee felt the need to caution him.
It's not the first time that a controversial handball has blighted United against Spanish opposition this season, after they lost to Real Sociedad in the group stages at home, thanks to a contentious penalty decision.
Still, at that point they held a two goal lead over their opponents and looked certain to qualify for the semi-finals, now they could be without five important players when they go to Seville in a week's time.