Erik ten Hag was left furious after a controversial late penalty saw West Ham inflict a damaging 2-1 defeat on Manchester United.
Jarrod Bowen scored the winner from the spot two minutes into stoppage time after a long VAR review for Matthijs de Ligt's challenge on Danny Ings.
Referee David Coote took his time in studying the pitchside monitor before awarding the spot-kick, to the horror of United's underfire manager and his players.
In a curious match which will crank up the noise surrounding Ten Hag's future, United dominated a first half in which West Ham were terrible.
Yet Crysencio Summerville climbed off the bench at half-time to fire the Hammers into an unlikely lead.
That was quickly cancelled out by Casemiro's header, but VAR's dramatic late intervention cost United, and possibly Ten Hag, dearly.
United almost took the lead in less than two minutes when Christian Eriksen fed Bruno Fernandes, who squared the ball for Alejandro Garnacho to hit a first-time shot from the edge of the area which crashed against the crossbar.
Fernandes should have opened the scoring when he was left unmarked in the area to meet a lofted ball from Casemiro, but he sent his header over the top.
West Ham were leaving huge gaps at the back, but the next United opportunity provided a comical miss from Diogo Dalot.
Fernandes lifted the ball over the top and Dalot knocked it to the side of Lukasz Fabianski before bearing down on an empty goal, only to somehow blaze wide from 12 yards.
There was still time for Hammers midfielder Edson Alvarez to nod a corner against his own crossbar and Fabianski to claw out Casemiro's free header before a first half of breathtaking ineptitude, chiefly - but not solely - from the hosts, came to an end.
Changes from Hammers boss Julen Lopetegui - also under scrutiny following their slow start to the season - were inevitable and Lucas Paqueta, Konstantinos Mavropanos and the ineffective Carlos Soler were sacrificed.
Jean-Clair Todibo, Tomas Soucek and Summerville - whom many had expected to start in the wake of Mohammed Kudus' ban for his Tottenham meltdown - were sent on.
The winger's arrival lifted the team, and the crowd, and West Ham should have scored when Michail Antonio reached the byline and pulled the ball back to Emerson Palmieri, who missed his kick in front of goal.
However, West Ham did take the lead in the 74th minute when Bowen crossed towards Ings, who scuffed his shot across goal from where Summerville slid in to convert at the far post.
The summer signing from Leeds raced to the home dugout to celebrate his first Hammers goal with his suspended team-mate Kudus.
However, the lead lasted just seven minutes before Dalot's header back across goal was helped on by Joshua Zirkzee and nodded home by Casemiro.
But as time ticked down Ings tumbled in the area, and although play continued for some time and there were barely any protests from West Ham, a VAR check was called.
Coote eventually pointed to the spot, Bowen did the rest and United's season plumbed new depths in the process.
