Southampton are beaten 1-6 by Liverpool in the Capital One Cup quarter-final at St Mary's

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Not since losing 6-2 to Tottenham in March 1995 had Saints let in six on their own patch, but this was another miserable League Cup quarter-final for Ronald Koeman.

Daniel Sturridge reponded to manager Jurgen Klopp's subtle suggestions that he needed to consider playing even if not 100 per cent fit, the striker demonstrated masterful finishing ability with two elegant goals to put his team in control after Sadio Mane had headed Southampton into a first-minute lead.

With a hat-trick from Divock Origi - his first goals for the club - and a further finish from substitute Jordon Ibe, Klopp's team secured their place in the competition's final four and moved the manager ever nearer his first major trophy at the club.

Klopp is just two months into his reign after succeeding Brendan Rodgers who failed to win silverware in over three years.

Having featured as a substitute in Sunday's 1-0 win at Swansea, Sturridge returned to Liverpool's starting XI for the first time since the 1-1 draw at Everton on October 4, which proved to be Rodgers' last game as manager.

He started alongside Adam Lallana and Origi in a front three, but it was right-back Connor Randall, making his second senior appearance, who threatened to overshadow the striker's return for entirely the wrong reasons.

In struggling to prevent Ryan Bertrand's left-wing cross in the opening minute, Randall set the tone for Liverpool's sluggish early defending which very nearly cost them defeat. Bertrand's cross found Mane, and under little pressure the forward headed into the bottom right corner beyond deputy goalkeeper Adam Bogdan.

Randall was almost immediately again under pressure, this time when Dusan Tadic found the space to cross for Victor Wanyama, but despite having similar time and space to Mane from in front of goal, the midfielder headed at Bogdan who made a routine save.

Sturridge had looked worryingly short of confidence with his first touches, when he conceded possession and appeared reluctant to over-extend his fragile physique. With his next, however, he scored Liverpool's equalising goal, and not only showed why he is their most important player in the pursuit of winning the Capital One Cup and finishing in the Premier League's top four, but also why it is so important he remains fit for England at Euro 2016.

Joe Allen played the striker into the penalty area with a pass from midfield in the 25th minute, and after hesitating he showed exceptional composure to calmly place the ball across the face of goal and into the bottom right corner beyond Maarten Stekelenburg.

His second goal, four minutes later, was even more impressive. Emre Can showed vision to send the ball into the box with the outside of his boot, and Sturridge lost Cedric before putting Liverpool 2-1 up with a classy first-time shot.

When Moreno's powerful shot, from the edge of the area following Lallana's cleared corner, was deflected in by Origi in the 45th minute, Liverpool's progress into the semi-finals already began to feel secure.

Klopp appeared to feel similarly when, as a precaution, he replaced Sturridge with Ibe in the 59th minute, and had he any remaining doubt it would have vanished only nine minutes later when Origi extended their lead.

When Allen found Ibe, the forward played Origi in with a slide-rule ball into the box, and the now-confident Belgian powerfully struck his team's fourth into the roof of the net.

Eighteen minutes remained when Ibe, following a left-wing cross from Moreno, sent an equally powerful shot into the back of the net from just inside the area after chesting the ball to control, and even then Klopp's resurgent team had the time and desire to score again.

Substitute Brad Smith crossed, again from the left, deep into the penalty area towards Origi, and the striker routinely headed in to secure Liverpool's sixth, and his treble.