Leicester move second with a win
Chilwell taps home opener, before VAR sees Bertrand sent off for Saints
Ayoze Perez and Vardy with hat-tricks, Tielemens and Maddison also on target
Southampton into relegation zone
Foxes equal record Premier League win
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Southampton 0-5 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
You wonder if the Southampton players wanted to come out the second half. There are a lot of supporters who have stayed, they haven't gone home so Southampton need to give everything now for the fans and the manager.
Southampton 0-5 Leicester
Almost six straight away.
Maya Yoshida is caught napping on the ball and Jamie Vardy pounces, knocking the ball into the box but shooting too close to a grateful Angus Gunn.
Image source, Getty ImagesSouthampton 0-5 Leicester
Back under way at St Mary's!
It's striker Danny Ings and defender Jannik Vestergaard who have made way for Stephens and Danso.
Southampton 0-5 Leicester
You expect Brendan Rodgers will tell his team to keep going. His side scored four second half goals against Newcastle earlier this season following Isaac Hayden's 43rd minute dismissal.
In anticipation, Ralph Hassenhuttl is bringing on two defenders in Jack Stephens and Kevin Danso for the second half.
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Anders Svensson: We are a man down,but lack of effort from these clowns is what is getting me. Can't do basics. Every man and his dog knew we needed a commanding centre back in the summer, we spend what little money we do have on players like Adams to sit on the bench.
HT: Southampton 0-5 Leicester
Just getting hold of the ball will be Southampton's number one priority in the second half.
Image source, OptaHT: Southampton 0-5 Leicester
Leicester are just the second team in Premier League history to establish a five-goal lead in the first half of an away game after Manchester City managed the same feat against Burnley in April 2010.
Meanwhile, Southampton's record Premier League defeat was a 7-1 loss at Liverpool back in 1999.
There could be a fair number of records falling by full-time should Leicester choose to maintain their first half tempo.
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Celebcelery: Fingers will be pointed at Ralph Hasenhuttl but it's the players on the pitch who have raised the white flag. Shocking defending which has nothing to do with being down to 10 men.
Brendan Rodgers proving yet again what a good manager he is. Gets everything out of his players!!
Trevor Kirkpatrick
HT: Southampton 0-5 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
Southampton's defending has been shocking but you want to see the players, collectively, come together, roll their sleeves up and give it a right go. You have got to show a little bit more then what Southampton have shown. I really do feel sorry for the supporters that have turned out tonight.
HT: Southampton 0-5 Leicester
With his goal shortly before half-time, Jamie Vardy moves on to seven Premier League goals for the season.
Two more and he will move above Sergio Aguero and Pierre-Emerick Aubameyang as the league's outright top scorer.
On the evidence of the first half, that looks rather achievable.
Image source, Getty ImagesSouthampton 0-5 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
Forget about the 5-0 scoreline, Southampton need to roll their sleeves up now and show some character. Not just for themselves but for the manager and the fans. Otherwise this is going to get worse in the second-half.
Southampton 0-5 Leicester
The Leicester fans cheer as if the final whistle has gone.
It's only half-time, and they already have five.
Jamie Vardy
Leicester make it five in the first half.
Jamie Vardy, suprisingly not on the scoresheet during his side's first four goals, gets among the action, blasting the ball past Angus Gunn from the centre of the penalty area as teh Foxes carve Southampton apart once again.
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Tony Cook: This is the result of the previous Southampton board selling off all its assets and leaving players that just aren't premier league standard, I hope Les Reed & Ralph Krueger are pleased with themselves!
lfcway: This is shocking...Leicester 4-0 up and Vardy is not on the scoresheet.
Southampton 0-4 Leicester
Defeat tonight, which now looks entirely inevitable, would mean Southampton have won just two of their last 15 Premier League matches.
How long does Ralph Hasenhuttl realistically have to turn this around?
Southampton 0-3 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
Barnes and Chilwell have been fantastic for Leicester tonight. Two young, very exciting players.
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Jack Lovatt: Southampton's best hope is putting the sprinklers on at half time in the hope this is rained off!
Scott: Pretty sure Ralph Hasenhuttl just did a rain dance
Southampton 0-4 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
What a cross from Chiwell to pick Perez out. He hasn't just played it, he's picked the pass out. It's a great, great finish but Valery's body shape was so closed, he didn't even know what was going on around him.
Ayoze Perez
Too easy.
Leicester shift the ball quickly from right to left, where Ben Chilwell is waiting to swing in a lovely cross towards the back post.
The Southampton defence is caught ball-watching and Ayoze Perez glides in from the right to strike the ball powerfully into the roof of the net.
St Mary's is emptying.
Southampton 0-3 Leicester
It's almost four for Leicester!
Ben Chilwell finds Harvey Barnes and the winger's shot almost trickles beneath Saints goalkeeper Angus Gunn in the slippery conditions.
Gunn reacts quickly enough, pouncing on the loose ball behind him just as it appeared it might roll over the line.