Erik ten Hag blamed "three tough decisions" for Manchester United's 4-3 defeat in Copenhagen that leaves their chances of progressing to the Champions League knockouts in tatters.
United's Rasmus Hojlund scored twice against his former club but a red card shown to fellow United striker Marcus Rashford saw the tie swing in the Danes' favour.
Rashford was sent off after a VAR review late in the first half for catching Elias Jelert on the ankle, with Mohamed Elyounoussi quickly scoring before Diogo Goncalves levelled from the spot.
Bruno Fernandes’ penalty put the visitors back ahead in the second half, only for Lukas Lerager and substitute Roony Bardghji to score in a blockbuster conclusion to a chaotic match.
“It’s clear we’re very disappointed and because you play very good,” Ten Hag said. “I think we started the game so well. The best minutes of this season.
“We are winning the game and I think the red card changes everything. Then we concede two goals before half time, which should never have counted.
“First is offside, second a penalty and that is – in four games – four penalties against. I say three are very debatable."
Ten Hag described Rashford's sending-off as "harsh" and was annoyed by the slow motion and freeze frame shown to referee Donatas Rumsas by the VAR as he decided on Rashford’s red card.
“I think he went for the ball and the referee needs such a long time to make it a red card,” added the Dutchman.
“I think when you freeze it, it always looks worse. As I say, it takes them so long and they make a red card of it. I’m very disappointed about such decisions. I think the game is never meant to be like this.
“It has nothing to do with football. Decisions have to be made and I accept that also wrong decisions are made by some at this level."
Ten Hag said an offside player obscured goalkeeper Andre Onana’s vision when Elyounoussi scored and was aggrieved by the decision to award handball against Harry Maguire for Goncalves’ penalty.
“Three such tough decisions, you control the game and I think the game is never meant to be for that.”
The defeat leaves United bottom of Group A and knowing they will be unable to reach the Champions League knockout phase if they lose their penultimate match at Galatasaray at the end of November.
“This squad is resilient,” Ten Hag said. “The whole season, so many decisions are against us, so many setbacks for injuries.
“Every time there is a spirit, there is a fight and we will keep going because I am sure and I said to the lads it will turn – on one moment in the season it will turn in our favour.”
Copenhagen counterpart Jacob Neestrup admitted Rashford’s red card changed the dynamics of a win he felt his side deserved after their promising start to the group.
“I have never said in the first three rounds we have been unlucky,” the head coach said. “I’ve said it’s been a lack of quality.
“If there was something that was called luck in football, then we’ve got it today. But we also hunted.
“The early goal made us very, very shaky. We are the second best team on the pitch in the whole first half until the red card."