Declan Rice's long-range goal capped a stunning demolition of his former side West Ham as Arsenal claimed a 6-0 win at the London Stadium to stay within two points of leaders Liverpool.
The fixture was billed as a tough assignment for Mikel Arteta's side following two defeats to West Ham earlier in the season but the hosts completely capitulated as four goals in 15 first-half minutes sent many fans streaming towards the exits early.
William Saliba's header from Rice's corner set the wheels in motion, with Bukayo Saka adding a second from the penalty spot before Gabriel Magalhaes headed home another Rice set-piece and Leandro Trossard added a brilliantly-taken fourth.
Arsenal continued to tear through the abject hosts in the second half, adding two more goals in as many minutes as Saka capitalised on static defending to finish at the near post before Rice's brilliant curler from 25 yards out completed the rout.
The extraordinary victory, Arsenal's biggest in a Premier League away game, puts the Gunners level with second-placed Manchester City on goal difference, maintaining their title hopes following last Sunday's win over Liverpool.
For West Ham, meanwhile, it marks a dark day, the joint-heaviest home league defeat in their history extending their winless run to seven games and piling pressure on manager David Moyes.