The teenager has represented Cerro Porteno's first team on 21 occasions, and he is regarded to be one of the best young talents in South America, with a number of clubs believed to be keen on his signature.
The speculation surrounding Leon and a potential move to Man United has intensified over the last few hours, and according to journalist Pedro Torres, a move has now been agreed.
Torres, via X, claims that "the groundwork" is in place, with Leon set to move to Old Trafford in the summer of 2025.
Fellow journalist Roberto Rojas, meanwhile, has said that the transfer will cost in the region of £4.7m.
Man United 'confirm' deal for Leon
Transfer expert Fabrizio Romano has also commented on the move, saying on his official YouTube channel: "Now, Man United are really in advanced stages for Diego Leon. He will be able to join Manchester United in the summer of 2025.
"Jason Wilcox is taking care of this negotiation and the deal is really, really advanced. Almost there. It is just about the bonuses and then the 'Here We Go!' is expected soon for Diego Leon to join Man Utd."
Leon has been with Cerro Porteno since the age of 13, progressing through the various youth teams at the club before making his first-team debut in August 2024.
The left-back has now featured on 19 occasions this season in the league, scoring twice, and he is now set to become the first-ever Paraguayan to represent the 20-time English champions.
What has Leon said about possible Man United move?
"I have a huge expectation to play the Libertadores 2025," Leon recently told Deportes Uno when questioned on the transfer speculation. "I've seen about Manchester United's enquiry about me, but I don't know anything. Everything is handled by my agent."
Arsenal have also been credited with an interest in Leon, but Man United have seemingly now won the race.
"He's a player with a lot of promise, who happened to make this big jump into the first team at Cerro Porteño so quickly," journalist Rojas told transfermarkt. "He's definitely viewed highly because of his talent and recent performances for one of the biggest clubs in the country and occupying that left flank as a full-back has allowed him to be someone who can go onto the attack, start playing from the back and also be versatile."
Man United have again had issues at left-back this season, with Luke Shaw injured once more, while Tyrell Malacia is only just back from almost 18 months on the sidelines with a serious knee injury.
Leon is allegedly viewed by new Red Devils head coach Ruben Amorim as the perfect player to operate as a left-sided wing-back in his 3-4-3 formation, and he could become the first signing of the new era at the club.
Written by
Matt Law