The 20-year-old has been in impressive form for Los Che during the 2023-24 campaign, featuring on 17 occasions in all competitions, contributing three goals and one assist in the process.
Guerra has a contract at Mestalla until June 2027, with his release clause believed to be €100m (£85.7m), but according to Gazzetta dello Sport, Valencia would be willing to sell for approximately €40m (£34.2m) due to their financial problems.
The report claims that Juventus are preparing to make an offer of €25m (£21.4m), but it will not be enough to convince Valencia to let the youngster leave in 2024.
Manchester United have also been heavily linked with the Spain Under-21s international, and it is believed that the Red Devils will step up their interest in him next year.
Guerra, who is also thought to be of interest to Newcastle United, made his Valencia debut against Sevilla in La Liga in April.
The midfielder was officially promoted to the first team for the current season, and he has played 15 times in Spain's top flight in 2023-24, contributing three goals and one assist.
Despite signing him to a new contract over the summer, Valencia have allegedly accepted that they will be unable to keep hold of him on a long-term basis due to the interest in his services.
In September, Los Che head coach Ruben Baraja said that the midfielder must "keep calm and manage the situation" amid the growing speculation surrounding his future.
"The process with him has been very fast in every way," Baraja told reporters at the time. "He finished last season very well and this year he has been a protagonist in offensive actions such as scoring goals.
"He must keep calm and manage the situation, and we must help him focus on his daily work. You have to know how to handle all of this and he is doing that well."
Scott McTominay was heavily linked with a departure over the summer, but he has developed into a key player for Erik ten Hag's side this season, with his latest contribution seeing him score twice in Man United's 2-1 success over Chelsea in the league on Wednesday. body check tags ::