The Paraguayan would be Chelsea's first signing of the summer.
Chelsea have plenty of talented youngsters on their books at the moment, from all over the world.
That comes from their advanced scouting system and one player who has seemingly caught the eye of Chelsea is Paraguayan youngster Sergio Diaz.
It is reported by Tutto Mercato Web that the father of the player is in London to watch the game with Sunderland at Stamford Bridge, with negotiations about a move to the Premier League champions to take place afterward.
Diaz, who was linked with Manchester United and Liverpool in January by Metro, is considered one of the hottest talents in South America.
Chelsea are rumoured to be beating Italian side AS Roma to his signature.
Diaz is just 17-years-old but is already showing ability beyond his age. He is a regular in the first-team at Paraguayan side Cerro Porteno.
He is also playing for the Paraguay under-20 side and considering his exceptional talent, Chelsea would fancy getting a work permit for the player.
If not, he would join the long list of Chelsea youngsters currently out on loan away from the club.
That's of course, if they sign him.