Brighton piled the pressure on Everton manager Frank Lampard with an emphatic victory at Goodison Park.
Kaoru Mitoma gave the Seagulls the lead with a composed finish after Moises Caicedo picked out the Japan winger on the edge of the penalty area.
The Toffees, who were fortunate not to fall further behind when teenager Evan Ferguson struck the outside of the post, were booed off at half-time.
But they fell apart completely after the restart as Brighton scored three goals in a remarkable six-minute spell early in the second half.
Ferguson, making his full Premier League debut, sidefooted Jeremy Sarmiento’s low cross into the top corner before turning provider for Solly March to drill home the Seagulls’ third.
Idrissa Gueye’s atrocious backpass was then easily intercepted by Pascal Gross, who coolly beat Jordan Pickford with a chipped finish.
Demarai Gray converted a late penalty for Everton, but it was nothing more than a consolation on a miserable evening for the hosts and their supporters.
The final whistle was greeted by more boos from the home fans, who have seen their team win only one of their past 10 top-flight games.
Everton could drop into the Premier League’s bottom three on Wednesday if other results go against them, while Brighton move back up to eighth.