Manchester United was toppled from the Premier League summit by Manchester City after losing to Norwich, while its crosstown rival routed Aston Villa to top the standings for the first time this season.
United's third loss of the season was inflicted by former youth team player Anthony Pilkington, whose second-half header gave Norwich a 1-0 win.
Defending champion City moved a point ahead of United after recording the biggest win of the season, beating Villa 5-0 as Sergio Aguerro and Carlos Tevez each scored twice after David Silva's opener.
In a day of a drama, third-place Chelsea lost 2-1 as manager Roberto Di Matteo returned to former club West Bromwich Albion, which moved a point behind the European champions.
And in the north London derby, Arsenal came from behind to beat Tottenham 5-2 after Emmanuel Adebayor's sending off swung the game in his former team's favor.
The pressure increased on Queens Park Rangers manager Mark Hughes after his winless side lost 3-1 to Southampton to stay bottom. But Reading secured its first win, beating Everton 2-1, while Luis Suarez scored twice in Liverpool's 3-0 win over Wigan and Swansea won 2-1 at Newcastle.