A dramatic late Alexis Sanchez winner turned the tables on Rafa Benitez's struggling Newcastle as United completed a remarkable climb off the canvas victory.
In scenes reminiscent of last season's wins at the Etihad and Selhurst Park, the winless Magpies had raced into an early 2-0 lead, through goals from Kenedy and Japanese international Yoshiniro Muto, to seemingly pile the pressure on beleaguered boss Jose Mourinho.
Listless and ragged in a first half in which United were again lethargic and lifeless, the team were rejuvenated after half-time, as substitute Juan Mata swept home a free-kick before Anthony Martial levelled. The Reds lay siege to the Newcastle goal and were finally, improbably, rewarded through Alexis Sanchez - another substitute whom has been much criticised in a dire run of form that has come to epitomise United's collective shortcomings.
The Chilean rose to nod in Ashley Young's whipped-in delivery right on the 90 as Old Trafford erupted and Mourinho lived to fight another day.
The match had been dominated by talk of Jose's imminent departure, and that talk was only further assuaged as Newcastle hit United with a brutal one-two punch inside the opening ten minutes. A lunging Nemanja Matic failed to intercept in midfield before Young allowed Kenedy to turn, run the ball on to his left foot and fire in a well-taken finish.
Three minutes later, United were gripped by panic again as Jonjo Shelvey raced clear and teed up Muto, on his first league start for Benitez's men, to once more turn the hapless Young and bury the visitors second from close range.
Mourinho reacted quickly amid the carnage, sacrificing Eric Bailly after 19 minutes with Scott McTominay again pressed into service as a makeshift centre-half. Mohamed Diame flashed a shot wide from distance and the visitors also saw a penalty shout fall on deaf ears when Young handled in the box. David de Gea saved well from the dangerous Muto before the United keeper was soon called into action again, this time to beat away Shelvey's 25 yarder.
De Gea's opposite number Martin Dubravka denied Paul Pogba before half-time, and Jose made another change at the break as Marouane Fellaini came on to replace McTominay and Pogba dropped into an unfamiliar back three alongside Matic and Chris Smalling.
Marcus Rashford headed of target and Pogba went close again in a spell of United pressure - pressure that was rewarded as United found a foothold and set up a frantic finale. Sub Mata curled in a superb 20 yard free-kick and from then on we were in the ascendancy as Newcastle lost all semblance of belie and shape. Dubravka kept out a Fellaini header and then denied Smalling with his foot, United's tails were up and the visitors suddenly found themselves under siege. On 76 minutes came an equaliser made in France as Martial and Pogba linked up for the latter to find the former with a back-heel and he slammed home beyond Dubravka to bring United level.
Newcastle were hanging on now but were unable to resist as another sub played the decisive hand in the final minute. Sanchez was the Land of the Giants from six yards as he rose to plant Young's cross beyond the scrambling Slovakian for timely, match winning intervention.
Overall team performance: 6/10. Woeful in the first half, wonderful in the second.
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