"Carlos Alcaraz is a gift to tennis, just when it appeared that a golden era of the men's game was drawing to a close," says former world No 2 and fellow Spaniard Alex Corretja.
The retirement of 22-time Grand Slam champion Rafael Nadal after the end of 20-time Grand Slam champion Roger Federer's career left a huge hole in the men's game.
But Alcaraz, 22, has already taken his Grand Slam tally to six with this month's US Open triumph while forming an intense rivalry with Italian Jannik Sinner, who has four Grand Slams.
"It's a blessing to have a player like Carlos Alcaraz. He is truly a gift to the sport," Corretja told website BolaVIP.
"It is nearly a miracle to be honest. We have had so many great players in the past, but after Rafael Nadal, our legend of the sport, all of a sudden we have Carlos, who is comparable."
"He is winning Grand Slams, he is the world No 1. It is something very unexpected and (we are) very fortunate to have him."
Alcaraz reclaimed top spot in the rankings after beating Sinner in the New York final. He and Sinner have shared the past eight Grand Slams between them.
"I think we really need to appreciate it, because what he is doing is very, very difficult and he is only 22 years old and has already won six Grand Slams," Corretja said.
"He will win many more Grand Slams in the future. Everybody loves him because he is so natural. He is so humble and simple, and he says whatever he feels. He is very straightforward and acts very well. He is unique."