Two Shinji Okazaki goals helped Leicester City ease to a 4-1 victory over a hapless Southampton at St Mary's.
Leicester took time to grow into the game but they were unstoppable once they got going as Riyad Mahrez scored a great individual opener after 11 minutes.
Southampton could not cope with their opponents and allowed Okazaki and Andy King to score from close range to make it 3-0 before the break.
Saints pulled a goal back through Maya Yoshida but the game was all over when Okazaki turned in his second on 69 minutes to complete the scoring and secure Leicester's fourth straight league win.
Algerian Mahrez picked up the ball 40 yards from goal in the 11th minute and was allowed to run at the Saints defence until he got 20 yards from goal, where he fired a shot across Fraser Forster into the bottom corner.
It was all Leicester from that moment onwards and the lead was doubled in the 32nd minute when a corner was volleyed at goal by Christian Fuchs but it was blocked on the line, only to fall to Okazaki who poked home from close range.
Saints looked incapable of defending and it was soon 3-0 as Harry Maguire was allowed to chest down a free-kick, turn and get to the byline from where he sent the ball across the goalmouth to the back post for King to tap in the third.
Hojberg, Ward-Prowse, Redmond and Stephens dropped out for Southampton, replaced by Davis, Lemina, Soares and Boufal, as Pellegrino made four changes. There were three changes for Leicester as Puel left out Albrighton, Gray and Iborra, who were replaced by Fuchs, Okazaki and King.
Southampton were better after the break and pulled one back when Yoshida headed a corner across the box, through a number of bodies and into the net beyond Kasper Schmeichel.
Charlie Austin should have made it 3-2 when Ryan Bertrand sent in a perfect cross for the striker to tap in from six yards but Schmeichel spread himself and stopped the shot superbly.
Southampton: Forster (6), Soares (6), Yoshida (5), Van Dijk (6), Bertrand (6), Tadic (4), Davis (5), Lemina (5), Romeu (5), Boufal (4), Austin (5)
Subs: Ward-Prowse (5), Gabbiadini (5), Redmond (5)
Leicester: Schmeichel (7), Simpson (7), Morgan (7), Maguire (8), Fuchs (7), Chilwell (8), Mahrez (9), King (8), Ndidi (7), Vardy (8), Okazaki (9)
Subs: Gray (6), Albrighton (6), Ulloa (6).
Man of the match: Shinji Okazaki
Leicester finished the scoring when Cedric Soares misplaced a pass, allowing Jamie Vardy to break down the right and cross into the box for Okazaki to steer into the net.
- Since Claude Puel took charge of Leicester City for the first time on October 29, only Manchester City (21) and Burnley (18) have won more points in the Premier League than the Foxes (17).
- Leicester City scored four goals in an away Premier League game for the first time since drawing 4-4 with Spurs in February 2004.
- Five of Riyad Mahrez's last eight Premier League goals have been from outside the box - prior to this, his previous 21 were all scored from inside the box.
- Mahrez has been directly involved in nine Premier League goals this season (five goals, four assists) in 17 appearances, as many as he was involved in during the entirety of 2016/17 (9).
- Shinji Okazaki scored and assisted in a Premier League game for the first time.
- This match was the first in Premier League history to see two different Asian goalscorers (Okazaki for Leicester and Yoshida for Southampton).
Mauricio Pellegrino: "It was a really bad game from the beginning to the end. After we conceded the first goal, as we started the first 10 minutes well, but after this goal they were getting better and little by little our confidence was down and we gave the ball away all the time.
"For me it's a little bit concentration, don't be 100 per cent focused and at this level, you cannot be on the pitch, giving this advantage and sometimes you get an awful day like today and this is the reality.
"In the Premier League there are a group of teams that the difference between the bottom and the middle is three, four, five six points like at the end of last season, it's more or less the same. It's really tight, we need to fight for every point.
"Obviously we got the same feeling as the supporters because when we play like this we are a little bit surprised as three days before we played a really good game. But in football, in three days, everything changed."
Claude Puel: "My team is the most important thing. I approve of my players because we gave a fantastic game, very good first half for example. It was important to maintain the result in the second half.
"I think it's a good team with very good players and they deserve all the results against City or against Arsenal and just all the team ready to play a strong game against this team. It's a very good result for us.
"All is not perfect. We need to correct some things, we need to continue to improve and always progress.
"It was nice to see familiar faces when I came back here, I have a lot of friends. I appreciated all the players, all the staff and it was a good moment to see them. It's one result and I am sure they will come back for the next games."
Man of the match - Shinji Okazaki
The striker was a constant threat to Southampton as he chased endlessly and got himself into great positions to score. The only dampener for him was he was unable to complete his hat-trick as he completed a rare 90 minutes.
Southampton travel to Stamford Bridge to play Premier League champions Chelsea on Saturday at 3pm.
Leicester will host Crystal Palace at the same time at the weekend.