Manchester United moved level on points with fifth-placed Tottenham after victory at West Ham, who played for 75 minutes with 10 men following the controversial dismissal of Sofiane Feghouli.
Referee Mike Dean showed Feghouli a straight red card after the midfielder's 15th-minute challenge on Phil Jones.
Replays showed it was more of a coming together between two players committed to winning the ball than a reckless tackle meant to cause harm.
Antonio Valencia was guilty of an astonishing miss for the visitors before Juan Mata scored from 10 yards after a clever pass by fellow substitute Marcus Rashford.
Zlatan Ibrahimovic was one of three players offside when he doubled the lead after Pedro Obiang's clearance fell to Ander Herrera.
It was Jose Mourinho's side's sixth straight Premier League win and their seventh in all competitions.
The Hammers have beaten Bournemouth, Sunderland, Burnley and Hull at home this season, yet their hopes of claiming a first major scalp at London Stadium were undone by the fastest sending off in the Premier League this season.
There is no doubt Feghouli lost control of the ball and deserved a booking for his challenge on Jones.
But Dean, who sent off Southampton's Nathan Redmond in the 4-1 defeat by Tottenham on Wednesday, brandished a red card for the fifth time this season, much to the fury of West Ham boss Slaven Bilic.
Meanwhile, Jermain Defoe scored two penalties as Sunderland twice came from behind to earn a point against second-placed Liverpool.
The Reds took a deserved lead when Daniel Sturridge flicked in a header after Dejan Lovren's mishit shot.
Sunderland equalised six minutes later as Defoe scored from the spot following Ragnar Klavan's trip on Didier Ndong, before Sadio Mane put the visitors back ahead with a close-range finish.
However, Mane then handled in his own 18-yard box and Defoe converted the penalty to snatch an unlikely point.
-BBC