Marko Arnautovic put the game away in the 74th minute, beating de Gea on a one-on-one. No player is bigger than the club and if I'm happy with his work he plays, if I'm not happy he doesn't play.
Mourinho's problems with Pogba are just the latest in a series of fall outs he has had with members of the United squad in just over two seasons in charge.
"For many months people are asking for Martial", Mourinho told BT Sport about his choice of attackers. Indeed, you could argue the decision was strong management, paying no heed to a player's reputation and purely selecting on form.
On the left-wing, Anthony Martial was preferred in favour of £500,00 per week misfit Alexis Sanchez but after failing to produce once again, it seems Mourinho's patience with the Frenchman is running out quicker that fans' with the Portuguese.
Mourinho pointed the finger at the officials but, McTominay apart, admitted his side were also suffering from mental "fragility". The Hammers recorded a comprehensive 8-0 thrashing of Macclesfield Town in the League Cup on Tuesday to extend their run of recent good form to three matches unbeaten.
The team were lethargic, just as they had been at Brighton.
"[Scott] McTominay, Man United at that level?" It was unfair to ask the youngster to adapt to a new position against the excellent front three that West Ham have. Nobody trained better than Pogba this week, and tomorrow [Saturday] he plays, so end of story.
Anthony Martial's relationship with Mourinho hit an all-time low during the summer, when Pogba's fellow France worldwide was fined for reputedly leaving the club's pre-season American tour without permission to attend the birth of his baby son, something the player is understood to dispute. Admittedly, they came up against a defence with roughly the strength of wet newspaper, but nevertheless took advantage. If they can, early-season fears of calamity will feel like a lifetime ago.