The Telegraph have suggested that West Ham’s board are considering Bilic’s future, after their poor start to the season.
And Curbishley said: “Anyone around that bottom three is going to come under enormous pressure. If you consider that you lose 70 per cent of your income by getting relegated, it’s a massive blow.”
West Ham are currently just one point above the bottom three, and there are serious concerns around the London Stadium.
The Hammers have failed to replicate their displays from last season, when they pushed for a European spot.
West Ham lost their last match 3-2 against Tottenham Hotspur, after throwing away a lead in the closing stages.
The Hammers now have a tough run of fixtures over the coming weeks, meaning things could get worse before they get better.
West Ham take on Manchester United at the weekend, before facing matches against Arsenal and Liverpool.