The 31-year-old striker has scored 12 goals in 36 appearances for the Yellow Submarine this season but is unable to persuade them that this is form worth investing £16m in.
It’s put the Hammers on alert with the hope that the Rossoneri will be willing to deal at a lower price although Premier League rivals Everton are ready to reignite their interest
Last summer saw the striker heavily linked with Arsenal but the signings of Alexandre Lacazette, 25, and Pierre-Emerick Aubameyang, 29, put an end to the Gunners interest.
His time Castellon was the least productive of a prolific career. Having previously averaged a goal every other game for his clubs, to fall to one in three games is disappointing.
Bacca hopes it hasn’t upset his chances of travelling to Russia with the Colombia national squad for this summer’s World Cup finals in Brazil. He sits 8th in the list of top goalscorers for his country with 14 goals in 43 appearances.
With Milan looking to reinvigorate their squad, Bacca’s time at the San Siro is up. The World Cup finals might be his shop window for a move to another league.