Alexis Sanchez got a 14-minute hat-trick as Arsenal eased past West Ham United at London Stadium.
The Gunners took the lead on 24 minutes, when Sanchez raced through to square to Mesut Ozil to score.
Sanchez doubled Arsenal’s lead on 72 minutes from an angle after a neat turn from Shkodran Mustafi’s pass, before firing in his second in the 80th minute from the edge of the area.
West Ham hit back when Andy Carroll nodded in after Dimitri Payet’s free-kick had hit the woodwork.
Alex Oxlade-Chamberlain scored from distance to make it 4-1 before Sanchez moved joint-top of the scoring charts with 11 goals, racing through, dummying and chipping in.
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Arsenal rise to second, three points behind Chelsea, while West Ham are 17th with 11 points.
Man of the Match Alexis Sanchez