Tensions at West Ham reached boiling point during the 3-0 Premier League defeat against Burnley as some fans invaded the pitch while others vented their anger at the board.
A turbulent week off the pitch -- which has seen fans cancel a planned protest march, and then turn against each other as a second demonstration was arranged and subsequently shelved -- turned toxic at the London Stadium.
Ashley Barnes had just put Burnley ahead early in the second half when a fan ran into the middle of the pitch, left unchallenged until Hammers captain Mark Noble intervened and shoved him to the ground.
As that fan ran back towards the stands another two came on and were eventually led away by defender James Collins.
It was Burnley's second goal, scored by Chris Wood, which proved the final straw for hundreds of fans, who charged along the concourse between the tiers of the stadium they hate so much to gather underneath the directors' box to chant "sack the board" and "you destroyed our club."
Joint-owners David Gold and David Sullivan, whose decision to move the club from its old Upton Park ground to the former Olympic Stadium is behind the anger, are reported to have left their seats for their own safety.
A fourth supporter, meanwhile, had picked up a corner flag, run to the centre-circle and planted it in the ground.
Police had to be positioned along the touchline and specifically around the West Ham bench, where more disturbances appeared to take place.
Wood helped himself to a third goal as West Ham appear to be imploding on and off the pitch.
Yet there was little sign of the chaos to come as the match kicked off. A smattering of supporters had trooped along the proposed protest route, while in the stadium the mood was more apathy than antipathy.
There was even a minutes' applause in memory of the 25th anniversary of the death of Bobby Moore, with a mosaic in the crowd bearing his name and shirt number.
How things changed after a first half which West Ham had dominated, with Nick Pope making decent saves to deny Marko Arnautovic and Manuel Lanzini.
As the wheels began to come off the anger towards the board grew, and anarchy began to break out on the pitch and in the stands.