United manager Erik ten Hag felt its use to dismiss Marcus Rashford for planting his foot on the ankle of Elias Jelert "changed the game". At the time, the visitors led 2-0. "In real time it's just not a red," former United midfielder Paul Scholes told TNT Sports.

Referee Donatas Rumsas would be called to the pitchside monitor twice more in the game, to award a penalty to each side for handball - both described as "soft" by Scholes' ex-United team-mate and colleague in the TNT studio, Owen Hargreaves.

With United smarting from another chastening defeat which leaves them facing a huge task to qualify for the last 16, BBC Sport picks through the chaos and controversies in the Danish capital.

United see red

Everything seemed to be going swimmingly for United after arguably their most accomplished 25 minutes of the season at the start of Wednesday's game.

Rasmus Hojlund's two close-range finishes in a period of purpose and precision had the visitors in complete control.

Then, with 42 minutes on the clock, the referee was alerted to Rashford's indiscretion - the planting of his foot on Jelert's ankle in what appeared to be a mistimed attempt to shield the ball. A review and red card followed.

"I think first we played very good until the red card. The red card changed everything. Then it becomes a different game," said Ten Hag.

"It is a harsh decision - he was going for the ball. The review was over, then he went up to the screen. I think the referee was not sure."

Pundit Hargreaves was more forthright when asked if it was a red.

"Not in a million years," he said. "Marcus is just trying to put his leg out to protect the ball.

"When you see a still [picture] it looks horrendous, but in real time he's not trying to foul him. It's not malicious, it's just a foul, it's just clumsy.

"They have to stop re-refereeing these games like that because it's ruining it. That's where the game changed."

Scholes added: "It's understanding what Rashford is trying to do. He's accidentally stood on his leg.

"He's thinking he's planting his leg down and protecting the ball. It's not a nasty challenge and totally accidental.

"This is where the referee's understanding of the game has to come into question."

Paying the penalty

Ten Hag was also adamant the two goals conceded by his side to level the game before the break should not have counted, with VAR again involved.

"We concede two goals that shouldn't count," he said. "The first is offside - there is a player in front of [Andre] Onana. The second [the penalty], what can you do about that?

"We have to deal with many decisions against us in other games. That's how it is. But the season is long. At one point it will turn in our favour."

The first goal Ten Hag refers to was scored by Mohamed Elyounoussi, with Elias Achouri the man the United boss believed was obstructing the view of goalkeeper Andre Onana while in an offside position.

The second came in the middle of 13 added minutes in a first half delayed for lengthy periods by a protester on the pitch and a medical emergency in the crowd.

For this, VAR was again used to adjudge that Harry Maguire had handled while attempting to clear. Diogo Goncalves levelled from the spot.

In an first 25 minutes of a second half United again controlled, even with 10 men, the referee evened up the penalty count, with video technology utilised to decide that Lukas Lerager had handled. Bruno Fernandes duly slotted home to make it 3-2.

"Where the confusion comes in is if that's in England I don't think that's a penalty," said Hargreaves of the penalty Copenhagen conceded. "It needs to be aligned across Europe.

"It is incredibly harsh. I thought the Harry Maguire penalty was soft, and that was even softer.

"The whole VAR thing, the last couple of weeks it's got a little bit out of control. It's taking a little bit away from the game. We want to see games decided on the pitch and not on screens, and at the moment a lot of these games are being decided on screens.

"Whether you love or hate VAR, it's just becoming a bigger part of the game than we all thought.

"The Champions League is so amazing, the football is so amazing - the game shouldn't be slowed down and stopped. The reason these games are so good is the speed of the games, and we're slowing them down to a still on a screen."

There was still time for a sting in the tail of Wednesday's game, as poor defending by United allowed Lerager to level again before 17-year-old substitute Roony Bardghji struck the winner with three minutes of normal time left."I saw lots of positives, but in the end we lost some focus. It's hard when you play so long with 10 men," added Ten Hag.

"That [the opening of the game] was the best 20 minutes I saw from my side. Also with 10 we were still controlling the game. It's very disappointing. We fought so hard, played so good. Still we don't have one point."

What United have in total is three points in Group A, one less than Copenhagen and Galatasaray.

They next travel to Turkey to face Galatasaray, before a final home game with already-qualified Bayern Munich.