West Ham failed in a late bid to sign Atalanta striker Duvan Zapata on Deadline Day.
It is understood the club submitted a deal sheet to the Premier League, but failed to get the transfer over the line for the Colombia international.
The Hammers' interest in Zapata dates back to at least 2013, when he played for Estudiantes in Argentina.
Zapata was wanted by Newcastle as well, but the North East club were also unable to complete a deal.
West Ham finished the transfer window without bringing in any new arrivals, despite attempts to sign Manchester United's Jesse Lingard, Benfica's Darwin Nunez, Leeds' Raphinha and Reims teenager Hugo Ekitike.
What happened to Lingard deal?
United's board decided to keep Lingard, who is out of contract at the end of the season, despite Ralf Rangnick giving his blessing for the midfielder to leave on Monday amid interest from West Ham and Newcastle.
Lingard, whose contract expires in the summer, was keen to move before the window closed on Monday night.
The forward wants regular first-team football so he can play his way into Gareth Southgate's England squad ahead of this year's World Cup.
Lingard has started just two matches for United this season, none of which have come in the Premier League.
Why did Benfica turn down Nunez offers?
Benfica rejected West Ham's bid for striker Darwin Nunez after failing to agree a fee.
A fee was thought to have been agreed between the two clubs for the 22-year-old Uruguay international over the weekend but Benfica rejected West Ham's offer.
According to Sky in Italy, West Ham offered €45m (£37.43m) plus add ons, but this fell short of Benfica's valuation.
West Ham considered an improved offer but, with so little time left in the January window, it was difficult for a deal to be done logistically. Nunez is currently with the Uruguay squad for their World Cup qualifier against Venezuela on Tuesday.
Nunez has scored 20 goals in 25 appearances in all competitions for Benfica this season.
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