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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FT: Southampton 0-9 (nine) Leicester
Brendan Rodgers' side are up to second, ahead of champions Manchester City and now boast a better goal difference than leaders Liverpool.
They trail Jurgen Klopp's side, who face Tottenham on Sunday, by five points.
They also have a five-point cushion in the race for a Champions League spot.
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Martin Tooth: Utter humiliation. And the worst thing about it is that if we hadn’t sold the family silver and failed to adequately replace it, we could be doing what Leicester are doing. A shameful night for our club.
James Ballantyne: Leicester might do a Leicester this season.
FT: Southampton 0-9 Leicester
Leon Osman
Former Everton midfielder on BBC Radio 5 Live Sports Extra
From Southampton's point of view, apart from Bertrand's red card, not one other player received a yellow card tonight, they were so passive. They just allowed Leicester to play them off the park and they deserved everything they got tonight.
FT: Southampton 0-9 (nine) Leicester
With that, Leicester become only the second side in Premier League history to have two players score a hat-trick in the same game.
Only Arsenal have managed that one before - through Jermaine Pennant and Robert Pires in May 2003 - which also came against Southampton.
FT: Southampton 0-9 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
You've got the two aspects of the game today - a team, Leicester, full of confidence and quality players and then on the opposite side, a team like Southampton who just didn't look good enough and set-up well enough to cope with them.
Southampton 0-9 (nine) Leicester
Right, send us your thoughts on that one.
Just how far can Brendan Rodgers take Leicester this season?
Where do Southampton and Ralph Hasenhuttl go from here?
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Southampton 0-9 (nine) Leicester
All over.
Oh my goodness.
Where to start with that?!
Jamie Vardy
They've done it!
Hat-trick Jamie Vardy!
A record-equalling ninth for Leicester!
Unbelievable scenes!
Southampton 0-8 Leicester
This to equal the Premier League record win...
Southampton 0-8 Leicester
Jamie Vardy is brought down and Leicester have their chance for a ninth!
Southampton 0-8 Leicester
Leicester really, really want more.
Youri Tielemans tries his luck but can't quite catch the ball right on the bounce, while Angus Gunn collects Ben Chilwell's follow-up.
Southampton 0-8 Leicester
Tony Pulis has spoken a lot on 5 Live commentary tonight about Leicester's use of the flanks and here's the proof of the Foxes' dominance.
Image source, OptaSouthampton 0-8 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
Does Hasenhuttl get the players in for training tomorrow? The lads won't sleep tonight and Ralph will have to clear his own mind.
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Stephen Noakes: Is United's 9-0 record at risk tonight?...Not what I thought I'd be saying about this game.
To be fair to Hasenhuttl, he recognised their weakness was the flanks and he's addressed that in the second half.
Scott, Surrey
Southampton 0-8 Leicester
Credit to Southampton, they're still trying to play.
But Leicester just won't let them.
The Saints try to build some momentum but they're soon swarmed by blue shirts - and within seconds Leicester earn themselves a corner.
Wilfred Ndidi rises highest, but can't jump high enough to direct the cross towards goal.
Southampton 0-8 Leicester
Tony Pulis
Former Stoke and West Brom manager on BBC Radio 5 Live
Wonderful free-kick, the technique is fabulous and if I was Southampton, I would be trying to just keep the ball now.
Southampton 0-8 Leicester
This currently equals Southampton's biggest ever defeat, in any competition.
James Maddison
You fully expected that to go in.
What a night this is for Leicester City.
James Maddison picks his spot and curls a superb free-kick into the top-left corner.
So, so good. Perhaps even more impressive though is that you just expect him to score those now.
Southampton 0-7 Leicester
Leicester have a free-kick in a great position here on the edge of the D.
James Maddison is eyeing it up...
Southampton 0-7 Leicester
A nice one for those who love their niche stats...
Ayoze Perez is the first player to score a hat-trick in back-to-back Premier League appearances against a single opponent since Luis Suarez against Norwich City in September 2012.
He hadn't scored for the Foxes since his summer arrival from Newcastle.