River Plate will receive around €32 million for the sale of Enzo Fernandez to Chelsea, according to transfer guru Fabrizio Romano.
The Argentina international midfielder joined the Blues for around €120 million from Benfica last month.
River Plate inserted a 25% sell-on clause in the deal that saw the 22-year-old join the Portuguese club last summer.
Fernandez was sold for an initial €10m, with another €8m as add-ons.
Both clubs would not have imagined that his value would skyrocket within 12 months.
Chelsea were willing to activate his release clause and they signed him on transfer deadline day.
The Argentine Primera División were convinced Fernandez was going to secure a big move given his potential. However, it definitely came earlier than they would have envisaged.
The massive windfall will surely come in handy as they continue to produce some of the biggest talents on the planet.
The new Chelsea player will be eager to hit the ground running in the Premier League.
He is now the fifth-most expensive player in the world. The South American also holds the record for the most expensive British transfer.
Benfica received an initial £34m installment which will be followed by five further payments.
Fernandez made a name for himself at the World Cup in Qatar, playing a key role in helping his country win the tournament.
He signed an eight-and-a-half-year contract with Chelsea and has a lot to live up to. The Blues have struggled under manager Graham Potter this term and are currently tenth in the Premier League.
They splashed this cash during the transfer window and will hope Fernandez and co can get them firing on all cylinders.