Liverpool have extended their Premier League home winning streak against Arsenal to six with an easy 4-0 victory that lifts them to second in the table.
Sadio Mane met a perfect free-kick from Trent Alexander-Arnold in the 39th minute to plant a header across Arsenal goalkeeper Aaron Ramsdale for Liverpool's opening goal.
Ramsdale produced a string of spectacular saves to keep Juergen Klopp's strikers at bay, but he could do nothing to stop Diogo Jota skipping past him in the 52nd minute, after a dreadful misplaced pass from Arsenal defender Nuno Tavares.
Inevitably, Mohamed Salah got in on the act with a close-range volley from a Mane cross in the 73rd minute, before Takumi Minamino came off the bench to turn in a cross from Alexander-Arnold with his first touch in the 77th.
Arsenal showed a few flashes of resistance and attacking spirit in the first half - not least from manager Mikel Arteta, who squared up angrily with Klopp over a foul in an ugly touchline exchange that earned both yellow cards.
But the Londoners looked crushed at the end, their eight-game unbeaten run over and yet again leaving Anfield empty-handed. The result leaves them fifth in the league.
United's misery hits rock bottom
Manchester United have suffered a fourth defeat in five Premier League games, as they went down 4-1 at Watford, finishing the game with 10 men to pile more pressure on manager Ole Gunnar Solskjaer.
The visitors were punished for a ragged first-half display, with Joshua King and Ismaila Sarr on target for the hosts. Sarr also had a penalty saved by David De Gea, who then kept out Sarr's retake, after video replay showed a player was in the area.
Substitute Donny van de Beek inspired a revival after the break and halved the deficit in the 50th minute, but United's day was summed up, when defender Harry Maguire was sent off for a clumsy tackle with 20 minutes remaining.
Watford made absolutely sure of a crucial win with a grandstand finish, as stoppage-time goals by substitute Joao Pedro and Emmanuel Dennis sparked noisy celebrations from the Vicarage Road faithful.
United now face a crucial week, with a Champions League tie against Villarreal, before a trip to table-topping Chelsea next weekend. They are in seventh place with 17 points - 12 behind Chelsea - while 16th-placed Watford have 13 points from 12 games.
Elsewhere, American forward Christian Pulisic was back among the goals, as Premier League leaders Chelsea extended their advantage to six points with a comfortable 3-0 win at Leicester City.
The visitors raced into a two-goal lead inside 28 minutes, after Antonio Rudiger climbed highest from a corner to head home and N'Golo Kante arrowed in a rare goal.
Leicester improved after the break, but Chelsea remained in control and put the game to bed, when Pulisic, who has endured a frustrating, injury-interrupted season, stepped off the bench and scored in the 71st minute.
The victory - Chelsea's fifth from six away league games this season - moved the Blues onto 29 points, six clear of second-placed champions Manchester City, who play West Ham United.
For so long top-four challengers in the Premier League, Leicester are well off the pace in 12th, after their fifth loss of the season.
Reuters
