Wow, this one's tense, fiery and gripping.

A change for Liverpool, with Glen Johnson replacing the injured Mamadou Sakho in the back three.

Image source, AFP

Television replays pick up another still of that tangle between Diego Costa and Martin Skrtel, which ends with the striker's foot landing on the defender's shin before the defender flicks out. Naughty? It looks like it...

BBC Radio 5 live Danny Mills at Stamford Bridge

Image source, Reuters

"I said earlier on, Michael Oliver would lose control of this game, and that's exactly what happened. He's let too many things go, made some bad decisions, and now the referee is rattled. If you're going to say that Costa deserved to be sent off for his stamp, I think you have to say that Skrtel deserved to be sent off for that flick at Costa."

Mamadou Sakho plays a horrendous passback and puts Chelsea onto the attack. Oscar, however, is scythed down by Lucas and Liverpool are able to recover. The Reds midfielder is booked and a melee follows with Martin Skrtel and Diego Costa once again facing off after they challenge for the loose ball. Neither man is giving an inch tonight in that individual battle.

John Terry is involved, as is Simon Mignolet. Messy, very messy.

Image source, AP

Chelsea are penning Liverpool back with some sustained pressure now. Liverpool try to press their hosts back but it's the Blues who are on the front foot.

BBC Radio 5 live Danny Mills at Stamford Bridge

"I'm not overly convinced Chelsea losing Cesc Fabregas is a blow. Fabregas hasn't been at his influential best, and I just think Ramires, with his pace and power, might suit this style of game more."

Bad news for Chelsea. Cesc Fabregas appears to have been injured by John Terry as the two both went for the same ball in the middle of the park, and the playmaker goes off injured. Ramires is on in his place.

Chelsea win only their second corner of the evening when Eden Hazard's low ball is put out of play by Martin Skrtel. The cross comes into the box but fails to beat the first man.

BBC Radio 5 live Danny Mills at Stamford Bridge

Image source, AP

"Liverpool are playing a very high pressing game now, trying to unsettle Chelsea and not give them any time and space. I just feel that one goal will be enough for either team."

Philippe Coutinho is having a stormer - he spins Cesc Fabregas in the middle of the park and leaves the Chelsea man chasing shadows. He almost picks out Raheem Sterling with a great ball too, but Kurt Zouma's outstretched leg saves the hosts.

Image source, Getty Images

Now Steven Gerrard has words with referee Michael Oliver as Liverpool prepare to get us back under way. This game is ready to catch fire.

Guardian chief football writer Daniel Taylor:, external Dave Beasant is the half-time guest at Stamford Bridge. 'Who the heck are you?" LFC fans sing. Beasant re-enacts FA Cup save in front of away end.

Liverpool defender Jose Enrique:, external Great first-half by the team. If we keep working like this we will win this. Keep going!!!

It would seem that Phil in Greenwich (just below 20:31) has certainly started some debate......

Damian, London: If it goes that far Phil in Greenwich, Chelsea will have had an extra 30 minutes' home advantage. Balance.

Craig, Beaconsfield: To Phil in Greenwich - if it's 1-1 after 90 mins, Chelsea get extra time & pens with home advantage. It's not unfair, they're the rules.

Andy in Sheffield: Let's clear up this extra time business once and for all. The reason away goals only count at the end of extra time is to balance out the fact that the team playing at home in the second leg has 30 extra minutes on their home soil, which is an advantage over the team playing at home in the first leg which has only 90 minutes at home.

Azbob in London: To those people complaining that it's unfair that Liverpool would have an extra 30 mins to score an away goal, Chelsea would have an extra 30 mins of this tie at home.

In the tunnel, Jose Mourinho is giving plenty of chat to referee Michael Oliver. He's very animated as Oliver readjusts his headset and tries to ignore him. Fourth official Phil Dowd steps in and Mourinho takes his seat for the second half early.

Junaed Razaq:, external Liverpool fans have major problems with Costa going down easily but had none when Mr Suarez did it time and again. Interesting.

Roman Bolton:, external I'm not one to commend Liverpool, but wow, and Coutinho, he's a magician, so underrated by everyone in the game.

Image source, AFP

The Special One will, however, be impressed with the form of young Kurt Zouma. What a prospect.

Who will be the happier manager at half-time? Put it this way... I reckon Jose Mourinho won't be too pleased to see Liverpool's pressing game in such good working order, while Philippe Coutinho looks like a man who can.

Bolton manager Neil Lennon is staring just a second defeat in 14 matches right in the face, they now trail 3-0 at Rotherham as Paul Green has increased the deficit.

Derby County can move joint-top in the Championship but are scoreless with Blackburn, while in League One MK Dons can go top with a win at Scunthorpe. That is goalless.