Lingard struck what proved to be the winner at the start of the second half and though Spurs rallied they couldn't get the equaliser, leaving more questions than answers around Mourinho's future at the club.
How did the players on each side perform?
✔️ GOOD PERFORMANCE
Jesse Lingard: 7.2
The on-loan Manchester United winger has been a revelation since arriving at West Ham in the January window, and he scored a vital winner here in David Moyes' striker-less system.
He sprinted away from Davinson Sanchez to lash his finish across Hugo Lloris and find the far corner, an effort which survived a VAR review and meant that his team had a two-goal lead.
Only Harry Kane touched the ball inside the area more than Lingard in the contest, highlighting further his hybrid position in the team and means that with Sebastian Haller's sale to Ajax, Moyes' men haven't missed a beat from an attacking perspective.
❌ BAD PERFORMANCE
Erik Lamela: 5.9
Lamela continues to contribute very little to this Spurs team during his time on the pitch - and here he was hooked at half-time by Jose Mourinho.
The Argentine's main contribution was to pick up a booking - not for the first time and it won't be the last - as Tottenham failed to find any kind of attacking cohesion and failed to create any opportunities.
Tottenham looked far more of a threat with Gareth Bale on the pitch in the second half, with the Welshman lashing a thunderbolt of a shot off the crossbar, meaning Lamela's place in the starting XI is under even more threat than ever.
⭐ STAR MAN
Michail Antonio: 7.3
Another midfielder by trade who has been converted into a hugely impressive attacking option, Antonio continues to be a mainstay of Moyes' revolution.
It was his application that opened the scoring, flicking a shot towards Lloris' goal before being quick enough to react in a tight space and bundle the ball over the line for the opener.
While his impact in terms of touches was minimal, his battling qualities, being involved in 16 duels, gives defenders no room to relax and when he does get on the ball, he can make things happen.