Manuel Pellegrini branded West Ham's 2-0 home defeat by Everton their worst performance of the season.
For the fourth time this term the Hammers had the chance to climb into seventh place, and for the fourth time they blew it.
Instead, first-half goals from Kurt Zouma and Bernard saw a dominant Everton leapfrog West Ham and put them firmly in the hunt for the potential Europa League spot.
"We played very bad in both boxes," said Hammers boss Pellegrini. "We didn't create chances in their box, and in our box we conceded two goals.
"Everton also had chances to score more. It was one of those bad days.
"It was not only the worst home performance, it was the worst performance of the year - away or at home.
"What I worry about is that it's not the first time we have had the opportunity of being seventh. Maybe that pressure also affects their performance.
"We must find a way of thinking and playing as a big team."
Pellegrini has never previously failed to qualify for Europe since arriving on the continent and although determined to maintain that proud record with the Hammers this season, it seems nobody has told his players.
Indeed, on this evidence the fact West Ham are in with a chance of finishing as the 'best of the rest' serves as a damning indictment of the rest of the league.
Notoriously slow starters, West Ham found themselves behind with just five minutes on the clock for the fifth time this season.
Zouma was the latest beneficiary, with the defender losing Issa Diop at a corner before sending a downward header into the ground, up and over the head of Aaron Cresswell on the goal line.
Lukasz Fabianski denied Gylfi Sigurdsson, Bernard and Dominic Calvert-Lewin before Brazilian winger Bernard tapped in a first Premier League goal before half-time.
Pellegrini hauled off Pedro Obiang, Lucas Perez and, to a chorus of boos, Marko Arnautovic but still it was Everton who came closest to scoring in the second half when Richarlison's header crashed against the crossbar.
"I'm very satisfied," said Everton boss Marco Silva. "We are working to achieve this type of performance.
"It was 2-0 at half-time but could have been three, four or five. We controlled the second half and had the best chance to score.