Arsenal laid down an early marker in the Premier League title race by beating Manchester City 1-0 on Sunday, while Liverpool were held by Brighton in a pulsating 2-2 draw.
Gabriel Martinelli's deflected strike on 86 minutes handed the Gunners their first league victory over City since 2015 to leapfrog the champions into second place in the table.
City have now lost consecutive Premier League games for the first time in five years. "It feels like a big win," said Arsenal boss Mikel Arteta. "It is a special one. "It has been a long time since the club beat Manchester City.
We felt today could be the day, but we needed a big performance from everyone and we had that." The treble winners were made to pay for a lacklustre performance with Erling Haaland anonymous up front.