Unseeded Jakub Mensik of the Czech Republic recorded a 6-4, 7-6 (6) upset over top-seeded Andrey Rublev on Thursday to advance to the semifinals of the Qatar ExxonMobil Open in Doha.

Mensik, 18, reached his maiden tour-level semifinal after firing 10 aces to dispatch the Russian in 98 minutes. The victory over the World No. 5 marked Mensik’s first Top 5 win in his career. He is the youngest player to accomplish that feat since Carlos Alcarez of Spain toppled Stefanos Tsitsipas of Greece at the U.S. Open in 2021.

Mensik will continue his quest for glory against France’s Gael Monfils, who posted a 6-2, 6-4 win over countryman and third-seeded Ugo Humbert. With Thursday’s win, the 37-year-old Monfils became the oldest semifinalist in tournament history.

Also on Thursday, Australian Alexei Popyrin posted a 6-4, 6-4 win over fourth-seeded Alexander Bublik of Kazakhstan. Popyrin will face Russian Karen Khachanov, who led 3-0 over Emil Ruusuvuori before the Finland native retired from the match due to injury.

–Field Level Media