A few hundred of those got into the stadium and invaded the pitch during the protest, while another group made their frustrations clear at the Lowry, the team hotel in the city centre.

“It was a difficult day for us,” Solskjaer said as he spoke for the first time since the postponement.

“Of course we wanted to play, we wanted to beat Liverpool for the fans because our job has to be getting good performances, good results on the pitch.

“That’s the players’ focus, that’s my focus but, as I said before the game, we have to listen.

“We have to hear the fans’ voice. It’s everyone’s right to protest, it has to be in a civilised manner, though. It has to be in a peaceful manner.

“Unfortunately, when you break in, when police officers get injured, scarred for life, that’s too far. That’s one step too far.

“When it gets out of hand like this, it’s a police matter. It’s not about showing your opinions anymore.”

A Greater Manchester Police spokesman said on Tuesday that six officers were injured as flares were let off and bottles thrown, with one sustaining a fractured eye socket and another a facial wound.

A man has been charged for his behaviour outside the Lowry Hotel and the force spokesman said the incident had been referred to the Independent Office for Police Conduct to “ensure complete transparency and independence”.

“The right to protest peacefully, everyone’s got a human right to be heard and a voice to be heard, but it has to be peaceful,” Solskjaer said.

“When you step out of line, when you break into, on to the pitch and into dressing rooms, I think that’s one step too far and when it becomes police matters that’s not nice.

“It’s not been helped by certain individuals. I have to say that’s another part of it. But that’s your end of it (in the media).”

Sunday’s postponement is far from ideal preparation for Thursday’s shot at reaching the Europa League final after stumbling at the semi-final stage on four separate occasions over the last two seasons.

United head to Roma boasting a 6-2 lead from the first leg and Solskjaer will maintain a “laser focus on the football” amid talk of more protests from understandably angered fans.

“My job, my focus has to be on the results, but you don’t really need to be a rocket scientist to see that we have challenges and frictions and things that have to be dealt with within communication,” the Norwegian said as he looks to reach his first final as United boss.

“Other individuals than me of course have started already, discussing with the fans, communicating with fan groups, which is going to be massive for us going forward.

“I think the players have done terrific to be where they are.

“I would be sad if all the good work the players have done is disrupted, so our focus is on playing well and getting through to a final now.”

United co-chairman Joel Glazer apologised for the Super League debacle saying “we got it wrong” but brother Avram kept schtum when door-stepped by Sky News on Tuesday.

The Glazers were conspicuous by their absence at the emergency United fans forum held on Friday, when departing executive vice-chairman Ed Woodward apologised for the Super League move.

Asked whether the owners should speak directly to supporters, Solskjaer said: “I’ve been communicating with the owners. I’ve got an apology, personally.

“They’ve apologised to the fans that this came out. I know that there is communication between other individuals than me and the fans.

“As I said, it’s a difficult position to be in for me, this, because I’ve got to focus on the football.

“I’ve always had a good relationship and they listen to me and they do listen to the fans and I’m sure there’ll be better communication coming.”