Croatia's Mario Mandzukic applauds fans
The Hammers have agreed a fee with AC Milan for striker Bacca, according to Sky Sports, but are waiting for a response from the Colombian as their pursuit drags on.
West Ham manager Slaven Bilic
With the deal looking no closer to completion, West Ham are seemingly preparing for the worst, and have now started asking about other strikers in case Bacca does reject a move to East London.
Last week, Tutto Mercato Web cited claims from Italian newspaper Tuttosport, which claimed that West Ham were eyeing a possible move for Juventus hitman Mario Mandzukic.
Now, the Daily Mail claim that West Ham have actually contacted Juventus about a possible deal for the striker, in what would be a hugely ambitious move.
Valencia v Atletico Madrid: Mario Mandzukic in action with new West Ham signing Sofiane Feghouli
Formerly of Wolfsburg, Bayern Munich and Atletico Madrid, Mandzukic hit 13 goals for Juventus last season - including two goals in five Champions League games - but may be pushed out of the club once Juve's deal to sign Napoli hitman Gonzalo Higuain goes through.
With that in mind, West Ham are believed to have tested the water by asking Juventus about a deal for the 30-year-old striker, something manager Slaven Bilic would no doubt be interested in.
Whilst managing Croatia, Bilic handed Mandzukic his debut on the international stage, and securing a big-money deal would see the duo reunite in East London, with Mandzukic believed to be keen on a move to the capital.
A proven goalscorer in Germany, Spain and Italy, a move to the Premier League could be appealing to Mandzukic, and whilst he's a big-name player that a number of clubs would be interested in, the chance to work with Bilic again could put West Ham in a good position to land the marquee striker they've been looking for in Mandzukic.
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