London - Argentinian midfielder Manuel Lanzini has joined West Ham on a season-long loan from United Arab Emirates club Al Jazira.
The 22-year-old is the Premier League side's seventh signing of the close season and the club hold an option to make the deal permanent at the end of the season.
Lanzini has played four times for Argentina Under-20s and came through the same River Plate youth system that produced the likes of Ariel Ortega and Javier Mascherano.
"This is very emotional because it is one of the best teams I have ever signed for," Lanzini told West Ham TV on Wednesday.
"This is a new challenge for me and that can only help in the future. It will test my ability in one of the best leagues in the world, so I am looking forward to getting started.
Lanzini became the youngest foreign player to play in the UAE Arabian Gulf League, making his first appearance aged 21, and he helped Al Jazira finish runners-up last season with eight goals in 24 league games.
West Ham have already signed Dimitri Payet, Angelo Ogbonna, Pedro Obiang, Carl Jenkinson, Stephen Hendrie and Darren Randolph this summer.