Pressure on Jose Mourinho had intensified after four games without a win in all competitions, although the club had dismissed reports he would be sacked regardless of Saturday's result.It looked as though the manager's days could be numbered when Newcastle raced into a two-goal lead inside 10 minutes, but second-half goals from Juan Mata, Anthony Martial and substitute Sanchez sealed all three points in remarkable fashion.
Newcastle went in front for the first time in a league game this season only seven minutes in, as Kenedy ran onto Ayoze Perez's throughball, turned away from Ashley Young and curled past David de Gea.
It was 2-0 just three minutes later, Yoshinori Muto spinning beyond Young and firing home from 12 yards out, prompting Mourinho to bring on Mata for Eric Bailly in a drastic reshuffle of his side.
Marcus Rashford then headed a golden chance wide as sections of the United fans began to turn their ire towards the club's board, chanting in support of Mourinho and former captain Gary Neville, who criticised the club's hierarchy on Friday.
It could have been even worse for United before the break, with De Gea clawing away a header from Muto and Young perhaps lucky not to concede a penalty for blocking a free-kick with his arm – although Muto was likewise fortunate for escaping the same offence in his own box.
Mourinho jogged down the tunnel at half-time to considerable applause from the home fans, who should have been celebrating a goal five minutes after the restart, when Nemanja Matic blazed over the bar with the goal gaping after Martin Dubravka denied Paul Pogba.
Mata grabbed a lifeline 21 minutes from time with an excellent free-kick from 20 yards out, which seemed to spark some life back into the home side, and Martial made it 2-2 after combining brilliantly with Pogba before firing into the bottom-left corner.
United's pressure did not relent and Sanchez responded to his own critics with a fine header from Young's deep cross from the right, prompting resounding chants in support of Mourinho from the buoyant home crowd.
