With Arsene Wenger watching from the stands, Arsenal came from behind to see off West Ham United 3-1 at home and move seven points clear at the top of the Premier League.
Wenger was back at the Emirates Stadium for the first time since leaving the club in 2018 after 22 years in charge and saw Bukayo Saka, Gabriel Martinelli and Eddie Nketiah score in a rousing second-half comeback after a Said Benrahma penalty had given West Ham the lead.
The victory maintained Arsenal's 100% home record in the league this season and lifted them to 40 points from 15 games, seven clear of second-placed Newcastle United, who have played 16 matches. They are eight ahead of third-placed Manchester City, who have played 14.
Benrahma sent Arsenal goalkeeper Aaron Ramsdale the wrong way from the spot to put West Ham in front in the 27th minute after a foul by William Saliba on Jarrod Bowen.
The hosts were awarded a spot-kick at the end of the first half for handball against Aaron Creswell before referee Michael Oliver overturned his decision after a VAR review, ruling that the ball had struck the defender in the face.
Saka equalized from close range in the 53rd minute while Martinelli smashed the ball inside the near post six minutes later to put Arsenal in front.
Striker Nketiah, making his first league start of the season in the place of injured Gabriel Jesus, added a third in the 69th and Arsenal kept pushing to score again.
Arsenal were playing their first match since the season paused for the World Cup and their first since key striker Jesus was ruled out of action for three months with a knee injury while playing for Brazil in Qatar.
Any concerns the injury could derail Arsenal's push for a first title since 2004 would have been heightened when they found themselves trailing at halftime.
West Ham, who have not won away in the league since August, had done well to keep Mikel Arteta's side largely out of the area in the first half but their defense gave way once Arsenal found their groove after the break, helped by some fantastic service from Odegaard.
The Norwegian split the visiting defence with a low pass to the feet of Saka, who had time to calmly pick his spot and beat former Arsenal 'keeper Lukasz Fabianski.
Saka hardly celebrated the goal, instead picking the ball up and rushing back to the centre circle. Now level, Arsenal did not take long to take the lead, Granit Xhaka slipping a pass towards Martinelli, whose powerful strike flummoxed Fabianski.
Nketiah then clinched all three points with a confident strike, fed by another pass from Odegaard.