Arsenal beat Chelsea 3-1 to return to the top
The visitors, Chelsea, suffered their sixth consecutive loss under Frank Lampard.
Martin Odegaard scored the first two goals for Arsenal from Granit Xhaka crosses.
Gabriel Jesus added the third goal from close range for Arsenal in the first half.
Noni Madueke scored a consolation goal for Chelsea in the second half.
Arsenal dominated the first half and could have scored more goals.
The win lifted the mood around Arsenal after a four-game winless run and kept the title race alive, with Arsenal two points above Manchester City.