And we're under way in both Champions League ties.

Here we go!

Image source, Reuters

Almost time for kick off, here's a reminder of the teams.

Man City: Ederson, Walker, Otamendi, Laporte, Bernardo Silva, Fernandinho, De Bruyne, Silva, Sterling, Gabriel Jesus, Sane. Subs: Bravo, Kompany, Gundogan, Aguero, Delph, Zinchenko, Foden.

Liverpool: Karius, Alexander-Arnold, Lovren, van Dijk, Robertson, Oxlade-Chamberlain, Wijnaldum, Milner, Salah, Firmino, Mane. Subs: Mignolet, Clyne, Klavan, Moreno, Ings, Solanke, Woodburn.

Referee: Antonio Miguel Mateu Lahoz (Spain)

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live

Virgil van Dijk has brought a calmness, he's got experience for young player, but he relaxes players, tells them where to be, he's a voice on the pitch.

I think he has had an influence on the young players. Players like Trent Alexander-Arnold have been better since he has come to the club.

Great camera shot from inside the tunnel as the players walk out to be confronted by a sea of blue and white. The home fans are waving flags in their team's colours as the Champions League anthem blasts out over the speakers.

Brilliant atmosphere now. This is what Champions League knockout games are all about.

John: I wouldn’t be surprised if City make comeback. I have seen Barcelona made 6-1 comeback against PSG not long ago. Anything can happen.

Dougie: Inspiration for City from Klopp himself, two years ago 1-3 down v Dortmund "Even if it is not really likely, it is possible and we should try to do it." Wise words.

Manchester City fans have responded to the din the Liverpool fans were making and are now drowning out the noise from the away end. Great atmosphere building with kick off five minutes away.

Lionel Messi and Andres Iniesta tonight become the first players to play 100 Champions League matches together.

Image source, Reuters

James Horncastle
European football writer on the Euro Leagues Football Show

There is a chance of a comeback. It is a slim one. Roma believe because they thought they played well at the Nou Camp.

They scored own goals and were unlucky not to get a couple of penalties.

When most people would say the tie is gone, it was an odd decision to rotate and rest so many players at the weekend against Fiorentina.

It seems they believe in this exploit. They think they can do something - or at the very least frighten Barcelona.

Os: Anyone in the 'Has Pep lost the plot' camp? Gotta go for it I suppose. Relax, it's rush goalie and Ederson at left wing back!

Alex: Massive respect for Guardiola going full on with that line up. Us Liverpool fans also want a game, no stalemate here please.

Liverpool fans are loving life at the moment, they are making all the noise inside the Etihad as kick off approaches.

An early goal for Manchester City and the atmosphere could change quickly.

Folj: Guardiola playing three at the back without wing-backs will only make things worse against an attacking team like Liverpool. Salah to run the show again tonight

Robbie: Didn't Marcelo bielsa (pep's idol) play a narrow 3-1-3-3 when his Bilbao team thrashed United in the Europa league? Maybe there won't be any wing backs...

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live

Henderson is Liverpool's best presser. He sets everything up. Georginio Wijnaldum is not as good at that, but he is really good at retaining the ball, he wins clever free kicks and takes the pressure off them.

Image source, Getty Images

Liverpool are understandably favourites to reach the semi-finals of the Champions League for the first time since 2008 but there is one cause for concern.

The Reds have never won an away match against English opposition in European competition.

Their first away game to an English side was back in 1971 - when they faced Leeds in the 1970-71 Inter-Cities Fairs Cup and drew 0-0 - and in the nine games since then they have failed to pick up any wins on the road.

Chris Bevan
BBC Sport at Etihad Stadium

Image source, BBC Sport

It's been a grey day in Manchester but the clouds are clearing as the players emerge to warm up. A glimpse of a blue sky up there, maybe reflecting some of the guarded optimism from the City fans I spoke to on my way in.

Juliette Ferrington
BBC Radio 5 live at Etihad Stadium

Image source, BBC Sport

Ok, we didn’t see the Liverpool team coach arrive but they were in the stadium and the players were out on the pitch by the time the Manchester City team coach rolled into the Etihad.

Talking to fans outside as they rallied and Hi five’d the players there is a feeling amongst the City fans that this tie is beyond them.

There’s hope, but it’s the hope that kills you.

One of them told me: “We know how good we are. The feeling around this team this season is unbelievable. We’re absolutely not out of this game but it’s going to be tough.”

Another one said: “We have a lot of heroes in the squad and tonight they could cement that further. We got a chance to create history and overcome adversity. It’s an early goal we need.”

Listen to 5 live commentary on the game from 19:45 BST.

Pepe: Being 3-0 I’m still more nervous than my wedding day. Unlike my marriage I hope Liverpool can be successful!

Lee: Tonight is all dependent on Liverpool's mentality. If they play offensively and remain calm, they will score and they will go through. If they concede early and panic, City could punish them.

Final Score

Don't forget you can listen to our Champions League commentary tonight and watch all the scores as they come in across the English & Scottish leagues.

Press the Red Button on your TV or go to the BBC Sport website and click on 5 live Final Score.

Alan Green
BBC Radio 5 live at Etihad Stadium

I’m certainly not ruling Manchester City out of this tie despite the first leg scoreline. They are the best team in the country and are very ‘capable’ of getting themselves back in it.

However, it’s obvious in the two meetings at Anfield this season that Liverpool aren’t frightened. They play on the front foot and have an extraordinary striking trio. It makes me think they will score at least one goal which should put this quarter-final beyond City.

But I was here for the Manchester derby on Saturday and that proved what a crazy sport football can be.

Matt: Hard to imagine Man City can pull this off but I was in stands for the incredible Spurs 3 - 4 City in FA Cup in 2004. 3-0 down and 1 man down at half-time...

Dennis: If City score early and deny them an away goal, I can confidently bet on City to sail through. "In Pep we trust"