Ignacio Buse claimed his first-ever ATP Tour title after defeating Tommy Paul in three sets in the Hamburg Open final.

Qualifier Buse won 7-6 (8-6) 4-6 6-3 in just over three hours against the sixth seed in the ATP 500 tournament showpiece.

After Paul saved two break points in the opening game, the pair exchanged two breaks each as they were made to go through a tie-break in the first set.

The tie-break went in favour of Buse, who clinched the first with his third set point, but Paul's quality came to the fore in the second as he raced into a 4-0 lead.

The American did drop one service game, but he held his nerve to take the match to a decider, where Buse regained his rhythm.

He broke at the fifth time of asking in the second game, before converting another break point in the sixth, setting him well on his way to victory, which he sealed with his first championship point.

Elsewhere in Geneva, there was a better outcome for Paul's fellow American Learner Tien, who defeated Mariano Navone in the final.

Fourth-seed Tien came from behind to win 3-6 6-3 7-5, after defeating Alexander Bublik and Stefanos Tsitsipas en route to the showpiece.

Data Debrief: South American delight for Buse

Buse is the first qualifier to win an ATP Tour title since Valentin Vacherot won the Shanghai Masters in October 2025.

Buse is also the first Peruvian Tour title-winner since Luis Horna in 2007, while he is just the fourth male tour-level singles champion from South America, after Pablo Arraya, Jaime Yzaga and Horna.

Tien (20), meanwhile, is the youngest Geneva champion since 18-year-old Marc Rosset won in 1989, and he is the youngest American man to claim a tour-level win on European clay since 17-year-old Michael Chang won the French Open in 1989.