The Hammers agreed the fee with Milan a couple of weeks ago and the player’s representatives held talks with the club over a potential move.
With Bacca’s agent reportedly striking a three-year deal with the club, which would be worth £3.8million a year in wages, it was left to the player to decide if he wants to make the move.
But with the player admitting he harbours hopes of playing for a Champions League club only – and amid claims Arsenal were plotting a move – the player has kept West Ham – still his only viable option – hanging on.
AC Milan are more than happy to cash in on the Colombian, with the £26million sale needed to help fund Milan’s efforts to strengthen their squad in the transfer market.
And according to Italian newspaper Corriere Dello Sport, Milan have now told the hitman he must come to a conclusion on his future by Sunday.
Whilst the Hammers’ lack of Champions League football is holding back a deal, their possible Europa League inclusion could help their situation.
With Bacca waiting until after West Ham’s third qualifying round second leg tie on Thursday, the outcome of the tie may play a big role in Bacca’s decision.
Should West Ham overcome their 2-1 deficit against NK Domzale, it could help sway Bacca to east London with the lure of at least Europa League football at the Premier League club.