After a disappointing season last term, the West Ham board decided to back Bilic rather than sack him, enabling him to bring in Joe Hart, Pablo Zabaleta, Marko Arnautovic and Javier Hernandez to boost his squad.
However, results in the opening stages of this season have been poor. Whilst three successive away games is a tough start, due to West Ham's London Stadium being used for athletics, 4-0, 3-2 and 3-0 defeats at Manchester United, Southampton and Newcastle United respectively aren't good enough.
The defeat at Newcastle was particularly awful, and Sky Sports report that West Ham are now claiming that Bilic's position is under review, as the Hammers consider making an early season change in the dugout.
Whilst Newcastle boss Rafael Benitez could be a target, The Express claim that West Ham are likely to be back in the market for Fulham boss Slavisa Jokanovic, months after their initial interest.
Sky Sports claimed back in April that West Ham were keen to land Jokanovic if they decided to let Bilic go, but the Serbian ended up staying at Craven Cottage when Bilic's future was secured.
Jokanovic impressed last season, taking Fulham to the play-offs with an attractive brand of football, though he has been frustrated by the club's transfer policy, and Fulham have made a shaky start to the season.
West Ham may now choose to go back in for Jokanovic this summer should they choose to replace Bilic, offering him a chance in the Premier League having been replaced as Watford boss after winning promotion in 2015.
Fulham won't want to lose Jokanovic, but given his frustration over his lack of input in the club's signing, he may well fancy a move to the London Stadium.