RIO DE JANEIRO — Spanish teenager Carlos Alcaraz beat Argentina’s Diego Schwartzman 6-4, 6-2 to win the Rio Open on Sunday.

The 18-year-old Alcaraz overcame third-seeded Schwartzman in the final to the delight of Brazilian fans at the clay-court tournament.

The seventh-seeded Spaniard won his first professional match in Rio de Janeiro two years ago and his first tournament last year at Umag, Croatia, also on clay.

The 29-year-old Schwartzman said his younger rival is doing “an amazing job.”

“He is so young and is already achieving impressive things,” the Argentine said.

The Spaniard converted five of his six break points overall and dominated with impressive baseline play.

Alcaraz’s path to the title included upsetting top-seeded Matteo Berrettini in the quarterfinals and then beating another Italian, Fabio Fognini, in the semifinals.

Fitness was a key element of Sunday’s final. Both players had their quarterfinals and semifinals on Saturday due to heavy rain falling in Rio during the week.

Schwartzman had threatened not to play his semifinal match against countryman Francisco Cerundolo if he didn’t have enough time to rest after a lengthy quarterfinal against Spain’s Pablo Andujar.