West Ham confirmed that they have agreed a deal with Deportivo Maldonado to take Jonathan Calleri on a season-long loan.
The 22-year-old striker is expected to link up with the London club in the coming days after he was on duty at the Olympic Games with Argentina, who were knocked out at the group stages.
"We signed Calleri," Hammers boss Slaven Bilic told the club's official website. "Unfortunately for him but good for us Argentina were knocked out of the Olympics last night, they didn't pass the group stage so he should be here with us – not today, not tomorrow, but pretty soon, depending on work permit or whatever."
Bilic added that the acquisition of Calleri will add depth in attack for his side, with the Argentine set to compete with Diafra Sakho, Andy Carroll, Enner Valencia and Ashley Fletcher for a starting berth.
"We did the deal not a long time ago but not yesterday, and he is a top striker as well," the Croatian coach added. "You need a squad, of course you need a squad but it is about the balance."