Andy Carroll’s hat-trick for West Ham dealt another blow to Arsenal’s already slim title hopes, despite the Gunners fighting back to draw at Upton Park.
Arsenal are 10 points behind leaders Leicester with six games to play.
Mesut Ozil and Alexis Sanchez converted Alex Iwobi passes to put Arsenal 2-0 up but Carroll netted twice in 160 seconds to bring his side level by half-time.
A far-post header completed Carroll’s treble, before Laurent Koscielny hooked in Arsenal’s equaliser from 10 yards.
The hosts extended their unbeaten home run in the Premier League to 14 games but Slaven Bilic’s side remain sixth, two points behind fourth-placed Manchester City, who play West Bromwich Albion at 17:30 BST.