Having quietly worked his way through the men’s singles draw, but the up-and-coming phenom Jakub Mensik from the Czech Republic can potentially shock some seeds as the 2023 US Open progresses.
Mensik will play top-ranked American, No. 9 seed Taylor Fritz, in Round 3 on Friday, looking to claim his first-ever Top 10 win in his very young career.
Here are some quick facts on the young Czech qualifier.
He is the youngest player remaining in the men’s draw
Mensik, who celebates his 18th birthday today, began the tournament as a 17-year-old.
Not only is the second-youngest player in the men’s singles draw this year behind American Learner Tien (who turns 18 in December), he is the youngest player to make the Round 3 since Fabrice Santoro back in 1990.
WATCH: Jakub Mensik, Round 1 Press Conference
He is also the youngest man to win a main-draw match at the US Open since Borna Coric in 2014.
If he pulls off a true teenage dream, matching Emma Raducanu's 2021 feat of winning a major out of qualifying, he could become the youngest US Open champion in the Open Era.
He came through qualifying to make his Grand Slam debut
Due to great results on the ATP Challenger Tour this year, the world No. 206 was ranked just high enough to get into the US Open Qualifying Tournament.
Mensik took out former Top 10 player Fabio Fognini in three sets in Round 1, followed by wins over Leandro Riedi and countryman Zdenek Kolar to make his first Grand Slam main draw. The US Open is also his first main tour-level tournament.
En route to his Round 3 appearance, Mensik beat two Frenchmen: Gregoire Barrere in Round 1 and fellow qualifier Titouan Droguet in Round 2, both in four sets.
He has an esteemed ATP Challenger and junior tennis career
Before Mensik made his debut on the Grand Slam stage, he has proved on the Challenger and junior tours that he has the game to play on the biggest stages.
As a junior, he built quite the resume: With a overall junior record of 83-28, the former junior world No. 2 won four junior titles and was the 2022 Australian Open boys' singles runner-up. His best results at the other three junior Slams were the third round (US Open 2021, Roland Garros 2022) and second round at Wimbledon in 2022, where he also reached the semifinals in doubles.
In the last two years, the Czech has won a total of six titles: five on the ITF Futures Circut and one Challenger title that he won earlier this year at home in Prague. In 2023, Mensik is 33-17 on the Challenger tour and that match confidence is definitely showing. These results helped earn him a career-high ranking of No. 187 in late July.

He has wins over some notable tour names
The teenager may be making his pro-level tour debut in New York, but Mensik has already notched some wins over notable names.
In ATP Challengers this year, he took out tour veterans Fognini and Fernando Verdasco, and other main tour players including Facundo Bagnis, Dominik Koepfer and Radu Albot.