Carlos Alcaraz earned his first ATP Tour match win as a 16-year-old at the Rio Open presented by Claro two years ago. At the same tournament on Sunday, the 18-year-old Spaniard made more history.

The seventh-seeded Alcaraz defeated third-seeded Diego Schwartzman 6-4, 6-2 to become the youngest ATP 500 champion since the category was created in 2009. It is the second tour-level title of the teen’s career following his breakthrough in Umag last year.

“I can’t believe it, honestly. It has been a great week for me playing a great level,” Alcaraz said in his on-court interview. “First tournament on clay since a long time, so I’m really happy with the performance during the whole week. It’s an amazing feeling right now.”

When Alcaraz stunned countryman Albert Ramos-Vinolas in Rio de Janeiro two years ago, he was No. 406 in the ATP Rankings. With his big win Sunday, the teen broke into the top 20 for the first time.

After Schwartzman missed a final forehand return one hour and 27 minutes into the final, Alcaraz fell to his knees in celebration.

The reigning NextGen ATP Finals champion overwhelmed world No. 14 Schwartzman with his power and fearless play, winning 12 of the final 16 games.

Alcaraz converted five of his six break points in the match. Overall, he won 55 per cent of his return points to put constant pressure on his veteran opponent.

The pivotal moment came at 4-4 in the opener. Schwartzman, who played more than five-and-a-half hours of tennis on Saturday due to a schedule logjam following rain earlier in the week, battled hard to maintain contact with the seventh seed. But Alcaraz hit a stunning backhand passing shot from well behind the baseline to earn the deciding break of the set. From there, he seemed in control of the match.

The Spaniard immediately broke in the second set, but Schwartzman refused to go down without a fight, striking back in the next game. Alcaraz was determined as the rain began to fall in the Rio night, breaking again with a rocket-like forehand that the Argentine was unable to handle.

Like he did two years ago against Ramos-Vinolas, Alcaraz showed maturity beyond his years. Instead of letting the pressure of the moment get to him, he used his power, drop shots and trips to the net to finish the job.

“I think this is my game. It’s a lot of variety. It’s the key [to how] I won the match,” Alcaraz said. “I know how Diego plays and this was really important for me.”

It was an impressive week from Alcaraz, who lost his first set of the tournament on Tuesday against Jaume Munar by a lopsided 6-2 margin. But after that, the Spaniard played sensational tennis to shine on the South American clay.

Due to rain, he had to face two tough Italians — top seed Matteo Berrettini and former top 10 star Fabio Fognini — on Saturday. But Alcaraz defeated Berrettini in three sets and Fognini in straight sets to reach the final. Once there, Alcaraz brought his best to take down the third seed.

Schwartzman, who lifted the Rio de Janeiro trophy in 2018, was pursuing his fifth ATP Tour title. The Argentine also reached the final in Buenos Aires last week.

“I think the South American clay season gives me a lot of confidence, points and rhythm,” Schwartzman said.

“After Australia, I went back home not feeling very well. Physically I finished not in the best way in the first tournaments of the year. But then I made the semi-finals and two finals in South America, losing against I think the best opponents every tournament,” he added.