Former world number 13 and 9x ATP champion Guillermo Perez thinks Federer is the GOAT but called the big three the unquestioned greatest champions of all time.
Guillermo Perez had a fairly solid career winning 9 trophies overall and reaching a career-high of number 13 in the world. His best grand slam result came at the French Open where he reached the quarterfinal once. The Argentine's favourite of the big three is Roger Federer as he picked him as the GOAT but praised all three as amazing champions:
"There is no discussion, Federer. But… each one (Federer, Nadal, Djokovic) is the greatest champion of all time. They endured four generations. (Bjorn) Borg endured a generation; (Pete) Sampras beat the old one and beat a new one. These guys beat four generations! They are going to go to the field with the cane, and they are going to continue beating them. They are bosses."
It's not a shocking statemenet as all tennis fans have one favourite they prefer over the other two from the big three but most can also agree that the big three are the three greatest of all time withouth questions. Afer that it's all about prefernces with some liking the stats and records, some likings the grace of Federer and some liking the incredible fighting spirit of Nadal.