Southampton play host to Liverpool in the first leg of their EFL Cup semi-final tie at St Mary’s on Wednesday night, with both sides aiming to reach the Wembley final.

Saints come into the fixture in poor form, though, having lost three on the bounce in the Premier League – conceding nine in the process – while they twice lost the lead to draw 2-2 with Norwich City at Carrow Road in the third round of the FA Cup on Saturday.

However, they have beaten three top-flight sides already on their way to the last four in this competition, with the highlight being their 2-0 win against Arsenal at the Emirates Stadium last time out.

Claude Puel’s men will face a tough task against the Merseyside outfit, though, who are second in the Premier League and five points behind the leaders Chelsea.

Like their south coast opponents in midweek, the Reds face a replay in the FA Cup after a much-changed side could only draw 0-0 with League Two outfit Plymouth Argyle at Anfield on Sunday.

Here are FIVE key battles that will decide the outcome at St Mary’s…

Daniel Sturridge vs. Virgil van Dijk

While he has found first-team starts hard to come by this season, with Philippe Coutinho unlikely to be named in the side and Sadio Mane away at the Africa Cup of Nations, Sturridge should get the nod up top at St Mary’s.

The England international scored twice in a 6-1 thrashing of Southampton at St Mary’s in the same competition last season, and he will look to replicate that impressive goalscoring form on Wednesday.

However, he will come up against one of the most-wanted centre-backs in the Premier League in Van Dijk, who continues to impress with his aerial dominance and his comfort and quality on the ball.

While he is strong in defence, the Dutchman has also shown how he can be a threat at the other end of the pitch for the low-scoring Saints with goals against Tottenham and Norwich in the last couple of weeks.

Adam Lallana vs. Oriol Romeu

Despite his success with the Saints, Lallana always gets a mixed reception when he returns to St Mary’s and he will certainly be keen to silence the boo-boys on Wednesday night – and he is in the form to do exactly that.

The England international has been one of the best players in the Premier League this season - he has scored seven goals and picked up seven assists in 18 top flight appearances - and he will be looking to make another impact in an attacking sense in the semi-final tie.

He will come up against Oriol Romeu who has often been the deepest-lying Saints midfielder this season, tasked with protecting his back four.

The Spaniard will need to be at his best and most aware to stop an in-form Lallana.

Roberto Firmino vs. Cedric Soares

Earlier on in the campaign, the link-up play between Firmino, Adam Lallana, Philippe Coutinho and Sadio Mane was quite sublime at times, but with the latter definitely out and Coutinho a doubt, it will be up to the Brazilian to provide that attacking spark on Wednesday.

With the likes of Daniel Sturridge and Divock Origi looking for service, Firmino will need to put in an influential performance to break down a Saints defence that they couldn’t in a 0-0 draw at St Mary’s in the Premier League in November.

If he starts on the left-hand side, the attacker will come up against Euro 2016 winner Cedric Soares, in what will be an interesting battle.

The pacey Portuguese right-back came off with a head injury in the defeat to Liverpool’s rivals Everton at Goodison Park last week, but is expected to be fit enough to start for this huge tie.

Divock Origi vs. Ryan Bertrand

The Belgian has probably had more first-team minutes than he might have expected this season – often being preferred to Daniel Sturridge in attack – and Jurgen Klopp will likely give the forward a start in this clash at St Mary’s, if nothing else for his outstanding performance in the same competition last season.

Origi netted a hat-trick in the 6-1 thrashing of Saints in the quarter-finals of the League Cup in 2015, and he will want to show that same clinical finishing to help his side reach a Wembley final.

While he and Roberto Firmino are likely to switch wings throughout, Southampton defender Ryan Bertrand will be up against Origi at some stage, no doubt.

The England international is one of the south coast side’s most consistent performers and he has certainly stood up in an attacking sense in recent weeks, scoring the equaliser in the 3-1 win against Bournemouth while he also netted in the previous round of this competition – a 2-0 triumph against Arsenal at the Emirates.

Jay Rodriguez vs. Dejan Lovren

Similarly to Lallana, Lovren isn’t the most popular player when he returns to St Mary’s following the way in which he left the Saints to join Liverpool in 2014.

The centre-back has certainly come on leaps and bounds for the Reds this term after a dodgy spell last season, and he is the club’s first choice at the heart of the defence right now with Joel Matip still on the sidelines through injury.

The Croatian will come up against a Rodriguez that is slightly different to the one he played with before he moved to Anfield, with the attacker still struggling to get back to the form he was showing three years ago.

There have certainly been glimpses of him getting back to his best, though – think the brace against south coast neighbours Bournemouth last month – and he will need to get the better of Lovren on Wednesday night if he is to find the net again.