Learn more about the Czech teen chasing a Next Gen ATP Finals spot

Jan Kumstat is one of the fastest-rising stars on the ATP Challenger circuit.

The 19-year-old Czech has won three consecutive Challenger titles, becoming just the third teenager to complete a hat-trick of trophies at that level, joining elite company alongside Guillermo Coria and Grigor Dimitrov.

Even Kumstat has been caught off guard by his rapid rise.

“From the start of the season, I had a goal that it would be good to be in the Top 400,” said Kumstat, who on 28 July was World No. 508, a vast difference to where he is now at No. 186 in the PIF ATP Rankings following title runs at the Liberec, Hamburg and Prague Challengers — two of which came on home soil.

Surprises are nothing new for Kumstat. It was only two and a half years ago, at the Australian Open, that he first began to view tennis as a potential career path. Kumstat reached the 2024 boys’ singles final in Melbourne (l. Rei Sakamoto), a breakthrough run that opened his eyes to what might be possible.

“At that moment, I think I was playing just for fun and practising for fun,” Kumstat recalled. “But after that final, that was the day that I said, ‘I want to be a professional tennis player’.”

Born and raised in Prostejov in south-central Czechia — the same hometown as Jakub Mensik — Kumstat began playing tennis aged four alongside his uncle and aunt. Like many young Czechs, Kumstat grew up around multiple sports. His father played hockey, while his mother played volleyball. Kumstat played football until his teenage years.

Competing last month in Liberec, Kumstat was making just his 11th appearance at ATP Challenger level. He went all the way to the title. For reference, his fellow Prostejov-native Mensik, a solidified Top-20 player, claimed his maiden Challenger title in his sixth outing.

Kumstat, meanwhile, is the third Czech teen to win three ATP Challenger titles, joining Tomas Berdych and Michal Tabara. He is riding a 17-match winning streak (including two qualifying matches at the Hamburg Challenger), after falling short in his first or second-round match in his first nine appearances at Challenger level.

Youngest To Win Three Consecutive Challenger Titles
Player Age Titles Span
Guillermo Coria 18 years, 10 months 2000: Lima, Sao Paulo, Montevideo 3 titles in 5 weeks
Grigor Dimitrov 19 years, 4 months 2010: Geneva, Bangkok-1, Bangkok-2 3 titles in 5 weeks
Jan Kumstat 19 years, 7 months 2026: Liberec, Hamburg, Prague 3 titles in 4 weeks

When reflecting on his recent success, Kumstat is quick to mention how his family has been in attendance throughout his title runs, including a last-minute dash to Germany.

“My parents and my uncle, with one friend, also came to the Hamburg final. I finished the semi-final Saturday around 4 p.m., and so in the evening they told me that they are coming the next day,” said Kumstat, now based in Czechia’s capital city Prague. “They came in the morning, we finished the match and they had a flight right after the match.

“They came to Prague, they were there all week. They also came to Liberec.”

Standing tall at 6’5”, Kumstat is aiming to qualify for the Next Gen ATP Finals. He is currently fifth in the PIF ATP Live Next Gen Race. Rafael Jodar currently leads the 20-and-under pack, with Joao Fonseca, Martin Landaluce and Joel Schwaerzler following, respectively.

“After the first [title], I know that I was like 15th in the Race, but after these past two tournaments, it is my goal to play in the Next Gen Finals,” said the 2007-born Kumstat, who grew up idolising Swiss icon Roger Federer. “There is a big chance to play. That’s the goal now.”

Jan Kumstat wins his third consecutive ATP Challenger title.Jan Kumstat wins the ATP Challenger 75 event in Prague. Credit: Martin Sidorjak