SIOUX FALLS, S.D., October 29, 2026 (Media Release)
Dylan Dietrich of Switzerland, the No. 1 collegiate player in the country at the University of Virginia, upset top seed and World No. 94 Jenson Brooksby 6-3, 6-3, on Wednesday to reach the quarterfinals at the MarketBeat Open.
Dietrich, a 22-year-old senior, was a former teammate for one season of Spanish sensation Rafael Jodar. Dietrich, ranked No. 254, was playing a Top 100 opponent for the first time in his career. Since July 20, the Zurich native has compiled a 15-3 record in his last five tournaments, highlighted by his first career Challenger title in Columbus, Ohio on Oct. 4.
Dietrich broke twice in the opening set and in the second game of the second set to secure the win. He only faced one break point in the 1 hour, 12 minute match while converting three of seven break points.
Dietrich will next face former World No. 39 J.J. Wolf in the quarterfinals on Friday. Wolf advanced to his fourth Challenger quarterfinal of the season with a 7-6(7), 7-6(3) win over Daniel Milavsky of Boston. Wolf, who was sidelined for a year due to a right shoulder injury he suffered in Delray Beach in February 2025, is nearly back in the Top 200 (No. 201 in ATP Live Rankings) after being unranked in February this year.
JJ Wolf showing off his skills 🎩
The American switches hands for a forehand winner in Sioux Falls!
#ATPChallenger | @usta https://t.co/Bub1VvuZac
— ATP Challenger (@ATPChallenger) October 28, 2026
Unseeded Aidan Mayo reached his third straight Challenger quarterfinal and fifth overall this season as he beat No. 8 seed Maks Kasnikowski of Poland 6-2, 6-7(4), 7-5. The 23-year-old Sacramento native will face 19-year-old Dutchman Mees Rottgering, who posted a 6-4, 7-6(3) victory over wild card Kaylan Bigun of Los Angeles. Rottgering, who is a sophomore at Wake Forest Univ., advanced to his third straight Challenger quarterfinal and he is 15th in the Next Gen Race to Reggio Calabria standings.
On Thursday, the final four second round matches will be played with No. 2 seed Valentin Royer of France taking on Slovenian qualifier Sebastian Dominko, No. 5 seed Liam Draxl of Canada plays qualifier Daniil Ostapenkov of Belarus and No. 3 Darwin Blanch takes on Mitchell Krueger of Dallas. On Kwik Star Stadium, Max Hans Rehberg of Germany faces Stefan Kozlov of Pembroke Pines, Fla.
