Atletico Madrid have announced the signing of teenage defender Nehuen Perez from Argentinos Juniors.

The 18-year-old centre-back has signed a six-year contract to move to the LaLiga side.

Perez, an Argentina Under-17 international, trained with Jorge Sampaoli's side in Russia during their unsuccessful World Cup campaign.

Atletico have also confirmed Bernard Mensah will join Kayserispor on loan for the 2018-19 season.