Spain's Nicolas Almagro beat top-seeded compatriot Carlos Moya 7-6, 3-6, 7-5 to win the Brazil Open on Sunday.
The 22-year-old Almagro used his aggressive style and superior fitness to wear down the experienced Moya and claim his third ATP title.
Almagro, 31st in the world rankings and seeded second, dropped just one set on his way to the final and was bursting with energy despite the sapping heat.
Moya, 31, had survived four three-set matches in the tournament and he used his guile and clever shot selection to ease into an early 3-1 lead.
Almagro upped the tempo, however, and the set went to a tiebreak, which the younger player clinched 7-4 with a rare ace.
Moya, 18th in the rankings, took the second set convincingly as Almagro became distracted by a succession of disputed line calls.
He calmed down in the final set and broke Moya's serve again to lead 5-4 and although Moya broke back Almagro took the next two games to seal victory in two hours and 27 minutes.
"It has been a special having my whole family here. I am a bit tired but happy to be able to celebrate with my family before starting my preparations for the Buenos Aires Cup," Almagro said in a televised interview.
"Carlos is a great player and a great person. Either of us could have been champion today but luck helped me carry it off," Almagro said.