London - Everton have signed defender Ramiro Mori from River Plate on a five-year deal for a fee of £9.5 million, according to a statement on the Premier League club's website.
The 24-year-old, who was part of the team that won the Copa Libertadores earlier this year, becomes only the second Argentine to represent the Toffees after Denis Stracqualursi.
He has scored 10 goals in 108 appearances for River Plate.
Mori's signing follows the arrivals of Tom Cleverly, Gerard Deulofeu, David Henen, Mason Holgate and Leandro Rodriguez at Everton.
The left-footed centre-half made his international debut with Argentina in March.