2023: First Challenger doubles final In August, Buse reached his first Challenger doubles final in
Lima partnering with
Jorge Panta.
2024: First Challenger singles final, top 250 In February, Buse received a wildcard for the qualifying competition at the
2024 Chile Open. In August, he reached his first Challenger singles final in
Como, losing to
Gabriel Debru in the final.
2025: Major, ATP and Top 125 debuts In February, Buse made his
ATP Tour debut at the
2025 Chile Open, where he received a main draw wildcard. He lost in the first round to eventual champion
Laslo Djere. In April, Buse reached the semifinals at the
Aix Provence Open as a qualifier, with wins over second seed
Luciano Darderi, his first top 50 win, and
Reilly Opelka. As a result, Buse rose close to 40 positions up, reaching the top 175 in the singles rankings on 5 May 2025. In June, Buse won his maiden
Challenger title at the
2025 Neckarcup 2.0, defeating
Guy den Ouden in the final. As a result he reached a career high singles ranking of world No. 152 on 9 June 2025. He reached his first ATP Tour semifinal by defeating
Kamil Majchrzak in the second round, and
Román Andrés Burruchaga in the quarterfinals. As a result Buse reached a new career-high in the top 150 on 21 July 2025. He lost to
Juan Manuel Cerúndolo in the semifinal. In August, Buse made his Grand Slam debut as a qualifier at the
US Open. He lost to sixth seed
Ben Shelton in the first round. In September, Buse won his second
Challenger title at the
Copa Sevilla, defeating
Genaro Olivieri in the final. At the
2025 Uruguay Open in Montevideo, Buse reached his third Challenger final of the season. As a result climbed to a career-high in the top 105 in the singles rankings on 17 November 2025.
2026: Top 60, First ATP 500 semifinal Buse reached the top 100 on 5 January 2026. Ranked No. 91 at the
2026 Rio Open, Buse reached a semifinal at the ATP 500-level for the first time and only his second time at the tour-level, with wins over Brazilian
Igor Marcondes, third seed and another local favorite
João Fonseca and
Matteo Berrettini. His run was ended by
Alejandro Tabilo in the semifinals in straight sets. In March, Buse made his
Masters 1000 debut at the
Miami Open as a qualifier, but lost in the first round to
Damir Džumhur. ==Personal life==