Man City beat Swansea 3-1 and ended the weekend with a perfect 10 victories under Pep Guardiola, including six in the Premier League.
Leaders Manchester City beat Swansea 3-1 to make it a perfect 10 victories under Pep Guardiola, including six in the Premier League, as they recorded their best start to a top-flight campaign.
City's victory was the perfect riposte to the Spaniard's old rival Jose Mourinho, who earlier saw his remodelled Manchester United sparkle without the dropped Wayne Rooney, thumping Premier League champions Leicester City 4-1.
On a day of 29 goals in eight games, both Manchester sides were outscored by Liverpool, who crushed Hull City 5-1 to take their tally to 24 in the past eight games.
Arsenal enjoyed the goal fest too, helping Arsene Wenger celebrate his 20th anniversary as their manager with three first-half goals sweeping aside London rivals Chelsea 3-0 at the Emirates Stadium.
Manchester City's victory owed much to Argentine striker Sergio Aguero, who scored twice to take his tally to 11 in six games in all competitions.
With Raheem Sterling adding a superb third goal, City increased their lead at the top of the table to four points, although an injury to Kevin De Bruyne took some gloss off their day.
Everton's unexpected 1-0 loss at Bournemouth meant Tottenham Hotspur moved into second place, on 14 points, after Son Heung-min scored both goals in the 2-1 win at Middlesbrough.
The Korean striker has now scored four times in three games to equal his tally for the whole of last season.
Arsenal are third on 13 points, ahead of Liverpool and Everton on goal difference
Manchester United moved into sixth on 12 points but Mourinho will not be looking too closely at the table just yet after going into the early kick-off under unexpected pressure following back-to-back league defeats.
His response was to drop Rooney, who cut a slightly bemused figure on the sidelines as United, and Paul Pogba, in particular, made light of his absence.
The world's most expensive footballer was at the centre of most of United's best moves, heading his first goal for the club on 42 minutes and starting the move that set up Juan Mata, Rooney's replacement, for another.
Three of the goals came via Danny Blind corners from the left as Leicester plunged to their third defeat, as many as they suffered in the whole of last season.
Although Mourinho said Rooney was "happy" after the game, it is hard to see how England's record scorer, who came on as a late substitute, will force his way back into the starting lineup.
"Of course, he is as happy as I am," Mourinho told reporters. "His team won. He is a big player for me, for United and for this country. I trust him completely."
Liverpool went one better than United at Anfield where Adam Lallana, James Milner (two penalties), Sadio Mane and a trademark special from outside the area by Philippe Coutinho brushed aside a Hull side demoralised by the first-half dismissal of Egyptian winger Ahmed Elmohamady for handball.
Wenger, who has suffered plenty of pain against Chelsea in his two-decade reign, could hardly have imagined an easier anniversary waltz as Arsenal wrapped it up before the break with goals from Alexis Sanchez, Theo Walcott and Mesut Ozil.
Chelsea, hamstrung by alarmingly feeble defending and toyed with in embarrassing fashion at times after the break, suffered their worst defeat to their neighbours in 19 years as Wenger and his men were rewarded with a standing ovation at the Emirates.
There was late drama at Stoke City, where West Bromwich Albion forward Salomon Rondon rescued a point for Tony Pulis in his 1,000th game as a manager, whose opposite number Mark Hughes was denied a first league win of the season.
With October not yet arrived, it is already looking tough at the bottom.
Another injury-time strike, this time by Christian Benteke, completed a remarkable comeback for Crystal Palace as they came from 2-0 down to win 3-2 at Sunderland, who are now in last place.
Man Utd 4-1 Leicester
Bournemouth 1-0 Everton
Liverpool 5-1 Hull
Middlesbrough 1-2 Tottenham
Stoke 1-1 West Brom
Sunderland 2-3 Crystal Palace
Swansea 1-3 Man City
Arsenal 3-0 Chelsea
West Ham v Southampton (Sun)
Burnley v Watford (Mon)