Erik ten Hag's side came into the game desperate to atone for their hugely damaging Champions League draw with Galatasaray in midweek, in which Andre Onana made two dismal errors, but they simply couldn't find a way to hurt Newcastle.
The Magpies raced out of the traps and had a dominant start, creating a multitude of chances. Kieran Trippier came closest, as he sent a brilliant 25-yard free-kick against the crossbar, with Andre Onana rooted to the spot.
It would get better for Newcastle, however, as just 10 minutes after the restart, Anthony Gordon scored the only goal of the game, as he ghosted in at the back post to finish Trippier's cross.
United could not get out of their own half at times, and Marcus Rashford was particularly guilty, as he offered next to nothing in attack and barely tracked back to help the defence before being hooked on the hour.
Ten Hag's side did have a late rally after Nick Pope injured his shoulder and was substituted, but it came to nothing, with an Antony goal ruled out after the ball bounced in off Harry Maguire, who was clearly offside.
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