The Red Devils striker put the hosts ahead six minutes into the game, but Dele Alli drew Tottenham level six minutes from half-time.
Moussa Sissoko brought down Rashford in the box nine minutes after play restarted, and the striker made no mistake from the spot to restore United’s lead.
Spurs were the second-best all-game, and their uninspiring performance ensured Mourinho’s first return to Old Trafford since last December didn’t end well.
Match of the Day presenter Gary Lineker and pundit Chris Sutton mocked the Portuguese after the game, reacting to Tottenham’s defeat thus on Twitter:
Mourinho’s struggles at Old Trafford continue.
— Gary Lineker (@GaryLineker) December 4, 2019
Humble Jose humbled by Ole…
— Chris Sutton (@chris_sutton73) December 4, 2019
Spurs have lost more Premier League matches (35) against the Red Devils than against any other team, and not even Jose could save them.
The Portuguese has won none of his last five away Premier League matches against United (D3 L2), failing to beat four different managers in that time.
Tottenham host Burnley at the weekend, and with nine points between them and Chelsea, they will look to bounce back from last night’s defeat with a victory in order to keep their top-four dreams alive.