As expected, Barcelona are on the attack from the off as Lamine Yamal feeds Fermín López, who finds Anthony Gordon inside the box but his first-time strike is blocked by Victor Lindelöf.

Amad tries to get on a run but his pass is blocked. United manage to retain possession but can't quite find a way into the box just yet.

Wayne Rooney
Former Manchester United striker on Amazon Prime

Kobbie Mainoo has to play when he's fit.

He has to play because he's a fantastic footballer, with a very good brain. He wants the ball, and he will take the ball in very tight areas. Move the ball very well, and he has scored a few goals as well.

I think for me, Mainoo is the future of this football club and you have to build the team around him.

He's played an awful lot of games already in such a short period of time, [but] this club needs players who know this football club. Know the city. That support Man Utd, but have that ability and temperament as well.

It is absolutely chucking it down in Barcelona.

The hosts have scored 29 goals in seven games at this stadium this season. Aston Villa are going to have to be defensively at their best to keep them quiet tonight.

Image source, Getty Images

Simon Stone
BBC Sport Manchester United reporter at Old Trafford

Manchester United were a goal down by now in their last two Champions League games.

Just saying.

Manchester United have lost seven of their last 10 Champions League games (W2 D1), their worst ever run across a 10-match stretch in the European Cup/UCL.

The Red Devils have only lost three in a row in the same campaign in this competition once before, in 2004-05.

Away we go in Manchester, Barcelona and across the continent.

Kasper Schmeichel
Former Leicester goalkeeper on BBC Radio 5 Live

Aston Villa are not on the same level as the elite teams but they do have an elite manager. They are so well drilled and it's not going to be easy by any stretch of the imagination.

Unai Emery's team are going to know down to the letter what they need to do to get a result here and they are more than capable of pulling that off.

Following the tragic passing of Tenerife striker Jesus de Miguel, a minutes silence is being held at all of the Champions League venues this evening.

Image source, Getty Images

Wayne Rooney
Former Manchester United striker on Amazon Prime

They want to see the players playing for the badge.

It's what football is all about.

You have bad games, you lose games of football, but the fans out there when it is a very difficult period for the club want [players] to show what it means to play for the club.

You just hope that these players understand that.

Simon Stone
BBC Sport Manchester United reporter at Old Trafford

Plenty of green and gold balloons in the air.

Not a massive protest but a symbolic one.

Manchester United fans are really not happy at present.

Image source, BBC Sport

Nick Mashiter
BBC Sport football news reporter at the Nou Camp

Following the tragic passing of Tenerife striker Jesus de Miguel and in respect for the victims of last month's train crash in Spain, the Champions League anthem is not being played at the Nou Camp.

Stephen Warnock
Former Liverpool defender on BBC Radio 5 Live at Nou Camp

I remember when I spoke to Ezri Konsa when I was out with Aston Villa in America about the manager and the level of detail, the way you learn the game.

A lot of people talk about Pep Guardiola and the way he sees the game different. I think Unai Emery is the same calibre. Emery is just an absolute genius at what he does.

The Champions League seems to stir something up for Manchester United's players.

It was after their 2-0 defeat by Atletico Madrid that Lisandro Martinez was critical of the club's hierarchy before United's 4-1 loss to Como sparked Bruno Fernandes' outburst against Michael Carrick and the staff.

Will there be any more loose lips in Europe this evening?

Wayne Rooney
Former Manchester United striker on Amazon Prime

I think Bruno [Fernandes] is always a threat. Bryan Mbeumo always gets one or two good chances in a game, but Bruno I would say is the main threat, and I think that shows the lack of a number nine.

Mbeumo does get chances Amad Diallo does get chances but here is nowhere near clinical enough. Matteus Cuha hasn't scored enough goals [either] really.

Manchester United have won all four of their home matches against Roma, their joint-best 100% record at home to an opponent in major European competition.

Will the Red Devils' extend that record?

Stephen Warnock
Former Liverpool defender on BBC Radio 5 Live at Nou Camp

I think the standards have massively dropped at Manchester United in the last couple of years. I think Michael Carrick brought those standards up last year but for whatever reason, whether it's a lack of confident or a lack of belief in what the manager is doing lately, or whether it's a few players throwing their toys out of the pram that has got to improve.

And it's got to be from both the manager and also within the changing room. There has to be heated discussions between the players to say this is unacceptable.

Simon Stone
BBC Sport Manchester United reporter at Old Trafford

Manchester United fans planned a green and gold balloon protest place as the teams came out.

You can already spot a fair few balloons in the Stretford End.

Manchester United have already started singing against the Glazer family and Sir Jim Ratcliffe - and plans for a new stadium - and director of football Jason Wilcox.

Image source, BBC Sport