Steve Bruce’s side fell behind on five minutes when Mohamed Elneny scored his first-ever top-flight goal.
Pierre-Emerick Aubameyang then continued his goalscoring run against the Magpies as the Gunners cruised to victory.
United remain nine points above the relegation zone ahead of the final four fixtures.
Our reporter Miles Starforth was at St James’s Park – and here’s how he rated each Newcastle player on a disappointing afternoon:
13. Joelinton (for Almiron, 72) - 5
Fielded on the right side of the attack. Photo: Stu Forster
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