Arsenal reclaimed fourth spot in the Premier League with an important victory at West Ham and dented the Hammers' own chances of securing European football next season.
The Gunners knew only a win would lift them back into the Champions League places after Tottenham beat Leicester earlier in the afternoon, but Mikel Arteta's side responded by grinding out a vital three points at London Stadium.
It was Arteta's centre-backs who came up with the goods, with Gabriel Magalhaes nodding the winner early in the second half after Rob Holding had opened the scoring from Bukayo Saka's 38th-minute corner.
Jarrod Bowen did pull the Hammers level just before the break, controlling Vladimir Coufal's cross and squeezing a strike into the bottom corner in what was a reward for a strong first-half performance.
But David Moyes' outfit failed to reach those levels after going behind for a second time - and defeat leaves them seventh, three points behind sixth-placed Manchester United with three games remaining.
Gunners goalkeeper Aaron Ramsdale said: "It was vital we won. I didn't know the [Tottenham] score before I went out but of course that was important if we want fourth or even third if we are looking higher.
"I didn't touch Jarrod Bowen, I was a yard away. He's a good lad Jarrod, he jumped straight up and was honest and said I didn't touch him. He thought I was going to make contact."
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