West Ham have signed defender Fabian Balbuena from Brazilian side Corinthians on a three-year deal.
Sky Sports News understands the fee for West Ham's sixth summer signing is £6.5m.
The Paraguay international told the club's official website: "I'm really excited for this new challenge and my target is to meet the demands of the Premier League.
"Obviously to be at West Ham is an extra motivation, and I want to do my best to help the team."
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West Ham's director of football Mario Husillos believes the 26-year-old, who captained Corinthians, will bring a wealth of experience to the side.
Husillos said: "We welcome Fabian to West Ham United. He is somebody we have monitored for a long time and we are very pleased to have taken the opportunity to sign him.
"He has won many individual honours and was often named one of the best central defenders in Brazil for his statistics.
"We believe he will improve our squad and our defensive qualities. He is the perfect age - a player for the present and the future - and he can be a very important player for many years at West Ham."
Balbuena made 136 appearances for Corinthians, scoring 11 goals in his three years at the Sao Paulo-based club, and helped them win the Brazilian championship in 2017.