Ruben Amorim’s honeymoon period as Man United manager is well and truly over following a chastening record of five defeats in his opening 10 games in charge.
The Red Devils were soon on their way to defeat number six when Alexander Isak headed home from Lewis Hall’s cross with a mere four minutes on the clock, with the Swede becoming the second Newcastle player to score in six consecutive Premier League games, matching the feat of Papiss Cissé in 2012.
Eddie Howe’s men were eager to press home their early advantage with further chances for Joelinton and Anthony Gordon, before Joelinton doubled the visitors’ lead.
Gordon played another telling role, this time teeing up the Brazilian to power his header past André Onana against Amorim’s lacklustre side.
Isak thought he had blasted home a third when Fabian Schar’s effort deflected into the frontman’s path, but the hosts’ blushes were spared by the assistant’s flag.
Moments later, Sandro Tonali’s close-range strike cannoned off the post in what was a torrid first half for the Red Devils.
However, Rasmus Hojlund gave United a rare moment of encouragement when his angled strike just cleared the far post, while Casemiro curled an effort wide moments before half-time.
Amorim’s side returned to the pitch with renewed intensity after the break, and Harry Maguire was unlucky not to halve the deficit when his stopping header from Diogo Dalot’s cross cannonned off the post.
Leny Yoro was next to come close when he headed wide from Christian Eriksen’s corner, but it was hardly relentless pressure, and Newcastle remained largely comfortable in seeing out the game’s closing stages.
The damage had been done in the first half, as the Magpies claimed a fourth straight top-flight win to nil for the first time since April 2012.
Howe’s side moved up to fifth and three points adrift of the top-four as a result of just their second-ever Premier League win at Old Trafford, while United suffered a third successive league defeat at home - a feat they’ve not succumbed to since a sobering run of form between December 1978 and February 1979 - hardly the ideal warm-up for a trip to their arch rivals Liverpool.