Goals from Nicolas Jackson and Cole Palmer secured another away win for Chelsea and raised serious questions about West Ham’s direction under new boss Julen Lopetegui.
The Spaniard looked furious as his expensively-assembled side crashed to a humiliating 3-0 defeat at home to their London rivals.
Jackson scored twice, the first within three minutes of kick-off, and Palmer added a third just moments into the second half.
It means all Lopetegui has to show for a £120million outlay on nine summer signings since replacing David Moyes is three home defeats, a scrappy win at Crystal Palace and a last-gasp draw with Fulham.
Just five matches in and the London Stadium crowd – many of whom wanted Moyes out despite the Scot overseeing the club’s most successful period in decades – turned on the new manager midway through the second half.
Lopetegui’s decision to substitute Crysencio Summerville, who in fairness was by no means the worst performer, was met with loud boos.
Moyes may well have been counting his blessings that he left when he did as he watched his old side unravel from the comfort of the beIN Sports studio.
All looks rosier in the Chelsea garden, by contrast, as Enzo Maresca’s side secured a third straight away win and climbed, for a few hours at least, to second in the table
The tone of a chastening afternoon for West Ham was set with Chelsea’s first attack as a harmless looking free-kick found Jackson down the left.
The Senegal frontman cut inside far too easily and stroked the ball through the legs of Hammers keeper Alphonse Areola at his near post.
Just 15 minutes later Jackson had his second, his fourth of the season and a fourth in three appearances against West Ham.
Moises Caicedo played the ball forward and Jackson strolled through the chasm left by Hammers centre-backs Max Kilman and Konstantinos Mavropanos before slotting it past Areola.
West Ham had been dreadful, although they did briefly threaten to halve the deficit with Jarrod Bowen lifting a good chance over the crossbar.
A VAR penalty check, after Summerville went down in the area after being pulled back by Wesley Fofana, went Chelsea’s way – ‘not sustained holding’ was the official explanation – before Mohammed Kudus had the ball in the net only to be flagged offside.
Whatever words of wisdom Lopetegui said at the break evidently had zero effect, as 70 seconds into the second half Chelsea had a third.
Jackson ran at West Ham’s hastily back-pedalling defence and slipped the ball to Palmer, who simply stepped away from Kilman and drove in his second goal of the campaign.
Areola prevented further embarrassment with a flying save to keep out a Christopher Nkunku header, but the damage had long since been done and the boos ringing out at full-time told a sorry tale for the hosts.