That’s according to James Blake with Nadal set to face Dominic Thiem in the Barcelona Open semi-final today.
Rafael Nadal is looking to become the first person to win the same event 12 times as he continues to dominate on clay.
The Spaniard has won 11 French Opens too, though was knocked out of the Monte Carlo Masters last week by Fabio Fognini.
His uncle Toni led Nadal to plenty of success before retiring from the coaching staff in 2017.
But Blake believes that having someone so close to Nadal while the 32-year-old was growing up has been key to his success.
“Uncle Toni was one of the greatest coaches,” Blake told Express Sport.
“I love the coaches like him who aren’t making a spectacle of themselves, they’re just doing their job.
“If you see what they’re talking about and the effect he has on Rafa you can see he’s doing a great job but he doesn’t need to let everyone know that.
“Uncle Toni would also direct him as a human being and help him grow up.
“Rafa was on tour as a 15 to 16-year-old, so he wasn’t fully mature and Uncle Toni was there to guide him.
“Rafa, with Federer is one of the greatest ambassadors and is one of the most genuine, respectful people.
“Having Uncle Toni helped him and now helping run the academy will help a lot of young people.”
Nadal is a 17-time Grand Slam champion and will be favourite to win the French Open later this summer.
Roger Federer is likely to pose a challenge with the Swiss star playing on clay for the first time in three seasons.
Novak Djokovic is current world No 1 and has won the last three Grand Slams.
And Toni believes that duo, as well as today’s opponent Thiem, will constantly pose challenges for Nadal.
When asked who are Nadal’s closest rivals, Toni recently told Ubitennis: “I would say Djokovic, Thiem and Federer.
“As for the young [players], there are six or seven who can have a great tournament.”