Image source, Reuters

Applause from the Liverpool fans as Philippe Coutinho comes on for his first appearance since 26 November. Georginio Wijnaldum makes way.

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Steve Claridge
Ex-Leicester striker on BBC Radio 5 Live

It shows the lack of opportunities that Liverpool have had, when they get one they snatch at it.

They have had no space to play in tonight. They just need to change it around. This is a test for the manager now. How can he change it, improve it?

Image source, AP

After a spell of passing the ball around the edge of the Southampton box, Adam Lallana snatches at a shot and sweeps it wide to the sound of ironic whistles from the home fans. 

Jurgen Klopp has seen enough. Philippe Coutinho is getting ready to come on.

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Marcus, London

From Mo, Manchester

Jon in Eastleigh

Ten minutes into the second half and I'm not convinced Liverpool will ever score if they continue to play the way they are doing. Nothing has changed from the first half, as they just run out of ideas in the final third. Distinct lack of tempo and creativity. 

Breakthrough! And it's a landmark goal. Luis Suarez bags his 100th Barca goal with a superb volley to haul the Copa del Rey holders ahead against Athletic. That means the visitors must score to avoid going out on away goals. Under 10 minutes until the break.

Paris St-Germain are just going in for a breather now, holding a 1-0 lead against visitors Metz in their Coupe de la Ligue quarter-final tie. 

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First attack of the half for Liverpool as James Milner sends a cross into the area, Virgil van Dijk clears and Southampton charge off on the breakaway and only a last-ditch clearance by Dejan Lovren from Jay Rodriguez's feet prevents the striker from getting a shot off on goal.

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... Steven Davis plays the free-kick short to Dusan Tadic, who drives the ball in and James Milner hacks it behind for a corner, which Loris Karius flaps at, but fails to get a touch and the ball drifts out of play.

James Milner has a couple of nibbles at Cedric Soares and in the end gives away a free-kick right on the edge of the Liverpool area. Good opportunity for the hosts...

Back under way at St Mary's. No changes for either side.

Deafening jeers from the home fans after Lionel Messi is hacked down about 30 yards from goal and the referee waves play on. Barca are in the middle of an ongoing row with La Liga bosses about the way they are treated by officials - that will add further fuel to the fire. Still goalless after 20 minutes with no real chances of note. 

Better news for Paris St Germain who have just taken a 1-0 lead against Metz through Thiago Silva, while Juventus head into the half-time break with a comfortable 2-0 advantage over Atalanta. 

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Thomas Livingstone: Two good-to-average saves from Loris Karius and he's God's gift to goalkeeping again? He'd be ashamed to let those in

Paul Lummis: He's had his critics, but Karius has been excellent so far. This game could be out of sight if not for him.

Phil McNulty
BBC Sport chief football writer at St. Mary's

Liverpool goalkeeper Loris Karius has had to deal with heavy criticism in his short Anfield career and was dropped after a nightmare performance in the 4-3 loss at Bournemouth.

The young German has, however, been outstanding tonight with two crucial saves from Nathan Redmond and a decisive, assured display.

And his second from Redmond right on half-time may yet prove vital in the context of this EFL Cup semi-final.

Image source, PA

Image source, Opta

Daniel Sturridge had fewer touches of the ball than any other Liverpool player in the first half, and none inside the box. Not a great half from the striker. In fact, only Loris Karius could arguably be happy with his performance.

Steve Claridge
Ex-Leicester striker on BBC Radio 5 Live

Southampton should be 2-0 up. I thought it would be a tough night for them but they have done everything you could expect of them. They have worked hard, created chances, they have been excellent. 

For 20 minutes Liverpool dominated and since then Southampton have had three half chances and one outstanding chance to get a second goal. Liverpool have square pegs in round holes. 

A risky scissor kick clearance by Cedric Soares as he sends the ball looping into his own area from by the corner flag. Fortunately, Fraser Forster is the man to get underneath it and the whistle goes for half time as he makes the catch.

So far so good for Southampton.

Just the one minute of time added on at the end of the first half. It looks like Southampton will head into the break with the advantage.

Paul Walmsley: Interesting how poor Firmino has been since Coutinho has been out of the team. He has been dire tonight.

Image source, Getty Images

Loris Karius is keeping Liverpool in the game at the moment. He's made a couple of very good saves, the latest to deny Nathan Redmond. Cedric's ball from the left runs through the Southampton man on the other side of the box, he's unmarked and has a bit of time but hits his shot too close to Karius, who thumps the ball away.

Image source, Reuters

Phil McNulty
BBC Sport chief football writer at St. Mary's

Liverpool manager Jurgen Klopp is his usual animated self in the technical area - but the body language is currently screaming out frustration as his side struggle to find a way back into this game.

Klopp's players are struggling to find any rhythm or cohesion.

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