West Ham have launched a £4 million bid for Mexico World Cup winger Pablo Barrera.
The Hammers believe they are close to a deal with Pumas, as the club that narrowly survived relegation embarks on a substantial rebuilding process under new manager Avram Grant.
Barrera had a cruciate ligament operation a year ago so he will undergo a strict medical before signing, but West Ham have been impressed by his three appearances as a substitute at the World Cup.
Celtic are also chasing Barrera, with Manchester United and Tottenham also linked with the 23-year-old, but the Hammers feel they have come up with the financial package to seal a deal.
Barrera recently said he would welcome the chance to play in the Premier League, telling Super Deporte: "I hope I can go abroad to play in a traditional club in Europe. I like football in Spain ... the Italian, English, I like various styles of the game. I aspire to that, I want to be in a good team, that's all I want."
West Ham co-owners David Sullivan and David Gold have also authorised a £11.1 million bid for Nice striker Loic Remy, 23, and continue their talks to try to land Santos star Neymar.
Lyon striker Frederic Piquionne interests West Brom, but the Hammers are expecting their bid of £1.2 million to be accepted and they have the edge of the newly promoted club in terms of salary.