Brendan Rodgers' Leicester moved second in the league as Ayoze Perez and Jamie Vardy both scored hat tricks at a wet St. Mary's stadium. "We actually found out at 6-0 when Jonny Evans came sprinting over and said if we carry on doing what we're doing we can get the record," Vardy told Sky Sports. "We've gone all the way to the end and managed to do it."
Southampton's Ryan Bertrand became the first Premier League player to receive a red card after a VAR review for an incident in the buildup to Leicester's first goal in the 10th minute. Leicester trails Liverpool by five points, and is ahead of third-place Manchester City by one point. Man City hosts Aston Villa on Saturday, and Liverpool hosts Tottenham in the 10th round's standout game on Sunday.
Ben Chilwell scored the opener for the Foxes when he side-footed home after Southampton goalkeeper Angus Gunn could only parry Harvey Barnes' initial effort. Southampton quickly received another blow when Bertrand was ejected on review for stretching over the top of the ball with his studs making contact with Perez's shin before the goal.
It got worse for the hosts when Leicester broke down the left to make it 2-0 in the 17th after Youri Tielemans fired in a low effort from the center of the box following good work by Barnes down the left wing.
Tielemans then set up Perez who made it 3-0 inside 20 minutes with his first goal for the club. Chilwell's cross picked out Perez, whose impressive strike put the visitors 4-0 ahead in the 39th, and Vardy had time to add a fifth before the break with Southampton jeered off the field.
Perez got his hat trick in the 57th. Barnes chipped the ball into the box, where Perez brought it down on his chest and slotted beyond Gunn. Vardy triggered an exodus of Saints fans with his second goal a minute later for 7-0, rising to head in Chilwell's cross.
With the rain continuing to pour and St Mary's rapidly emptying, Maddison added his name to the scoresheet in the 85th. His curling free kick from just outside the box made it 8-0 — the scoreline by which Manchester City beat Watford earlier in the season.
Vardy scored from the penalty spot right at the end for his hat trick as Leicester equaled the Premier League's record winning margin in stoppage time, after Vardy had been brought down by Jan Bednarek.
Southampton manager Ralph Hassenhuttl said: "I take 100% responsibility for this result. This cannot happen like this. For me, I've never had such an experience in my entire managing career." As well as matching Man United's 9-0 win against Ipswich, Friday's rout sets a new marker for EPL away victories, exceeding United's 8-1 win at Nottingham Forest in 1999.
Southampton, which had named an unchanged lineup for the game like Leicester, dropped into the relegation zone behind 17th-place Newcastle on goal difference. The Saints haven't won at home since April.
Southampton included a tribute to the late Leicester chairman Vichai Srivaddhanaprabha on the front of the match program, two days before the first anniversary of the helicopter crash which killed him and four other people.
"The main thing that Khun Vichai ever wanted from us was to fight and win and I think you can see tonight that we've done that in amounts beyond what we've ever seen playing-wise," said Vardy. "Credit to the boys and hopefully the boss is looking down on us."
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