Said Benrahma has failed his West Ham medical after a deal was agreed with Brentford to take the forward across London, with new discussions now taking place to find common ground on a revised fee.
A rip-roaring season in the Championship last term attracted plenty of interested suitors from the Premier League, with a departure from the Bees made more likely by the club's failure to secure promotion.
Crystal Palace and West Ham were the two clubs most heavily linked, but after a £25m deal was agreed with the Hammers, a move to the London Stadium appeared inevitable. 90min learned back in August that Arsenal were also keen on a deal.
However, as per Darren Lewis, that transfer has hit a snag with it revealed that Benrahma failed his medical on Friday, putting the switch in 'jeopardy'.
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West Ham do not feel they can meet Jesse Lingard's wage demands and he is now likely to return to Man Utd when his loan ends.
Work is now being done to negotiate a new fee after he failed his medical. Sami Mokbel states that Brentford are still keen to sell Benrahma, but they will have accept a less desirable financial package given the fitness of the forward. As it is, the deal is 'off', although there is still some time left to reach a conclusion.
A fee, in the region of £30m when accounting for add-ons, was agreed between the two parties, coming after 90min reported that the Hammers had lodged an opening offer of £17m. Discussions took place to reach an amicable solution, culminating in a mutual agreement that would see Benrahma undergo his medicals before the transfer deadline.
It has been a very quiet window in east London, with defender Vladimir Coufal joining from Slavia Prague for just over £5m, alongside fellow countryman Tomas Soucek, who made his loan deal from the same club permanent for £15m.
With the domestic window still open, West Ham also signed Craig Dawson from Watford on a season-long loan, but that could prove to be their final action of the window unless significant progress is made in the Benrahma deal.