The Spaniard has noted the Bianconeri's impressive transfer dealings over the summer and fears nobody will be able to stand in their way of lifting more trophies this term
The Bianconeri begin their bid for a third successive Serie A title at Sampdoria on August 25 after enjoying a fruitful summer transfer window that has also seen them secure the services of defender Angelo Ogbonna from Torino.
And though the Viola will be strengthened themsleves by the returning Giuseppe Rossi - who was bought from Villarreal last season while still recovering from a serious knee injury - and Germany striker Mario Gomez, Valero fears Juve will still have too much for the rest of Italy.
"Juve have made a great signing," he told La Gazzetta dello Sport when quizzed on Juve's purchase of Llorente. "Unfortunately for us, he will help Juve to more trophies.
"With Llorente and Tevez, Antonio Conte's club are, more than ever, favorites to win the Scudetto again."
The Spanish midfielder then expressed his love for Fiorentina and thanked them for their understanding as he mourned the loss of his mother over the summer, while adding that he hopes to have paved the way for his fellow countrymen to move to Italy.
He added: "It’s been hard. But staying at home, in my pain, would not help me. So I preferred to reach out to my team-mates immediately. Fiorentina is now my second family.
"Many of my countrymen ask me about Fiorentina. Many great players would want to come to Fiorentina. I'm happy to have paved the way for them. This may be the most important season of my career."
The 28-year-old moved to Florence from Villarreal in August 2012.