Jan Kumstat is one of the top rising stars on the ATP Challenger circuit, but what is his racquet and strings setup?
Jan Kumstat’s tennis racquet
Jan Kumstat’s racquet is a Yonex Ezone 98 (2025) with lead tape on the sides (3 and 9) and strung with Yonex Polytour Pro. We are unaware of Kumstat’s racquet specifications or string tension, so if you know, please share in the comments.
Born: January 2, 2007, in Prostejov, Czech Republic
Height: 1.96 m (6’5″)
Plays: Right-handed with a two-handed backhand
Current ranking: No. 186 in singles (also career high, August 2026)
Bio and Career
Born in Prostejov (same hometown as Jakub Mensik), he picked up a racket at age four but for a long time tennis was mostly fun and recreational for him. That changed at the 2024 Australian Open, when a deep junior run made him realise professional tennis was a realistic path.
Junior career highlights
- 2022 European Youth Olympic Festival – won gold in singles in Banska Bystrica
- 2023 Junior Davis Cup – part of the winning Czech team
- 2024 Australian Open Boys’ Singles – reached the final, losing to Rei Sakamoto 3–6, 7–6(7–2), 7–5
- 2025 Australian Open Boys’ Doubles – junior Grand Slam champion
Pro breakthrough
Kumstát spent most of the early 2026 season well outside the top 400 before an extraordinary run of form. He won three consecutive ATP Challenger titles, at Liberec, Hamburg, and Prague, becoming just the third teenager ever to complete a Challenger “three-peat,” alongside Guillermo Coria and Grigor Dimitrov. He’s now being talked about as a contender for a Next Gen ATP Finals spot.
