Jakub Mensik upset world number two Jannik Sinner in the quarter-finals of the Qatar Open in Doha on Thursday, ending the Italian’s impressive run of form. The 20-year-old Czech player secured a 7-6 (7-3), 2-6, 6-3 victory, preventing Sinner from reaching another final.
The result halts a sequence of 22 wins in 23 matches for Sinner, whose only previous defeat during that period came against Novak Djokovic in the semi-finals of the Australian Open last month. Sinner’s dominant 2025 saw him reach ten finals, culminating in victories at both the Australian Open and Wimbledon.
Mensik, currently ranked 16th in the world, dictated the first set, taking it to a tie-break which he won convincingly. Sinner responded strongly, leveling the match by claiming the second set 6-2. However, Mensik regained control in the deciding set, securing the win and a place in the semi-finals.
The Czech player will now face unseeded Frenchman Arthur Fils, who progressed to the semi-finals after defeating Mensik’s compatriot, Jiri Lehecka, 6-3, 6-3. This will be Mensik’s fourth ATP semi-final and his second of 2026, following his victory at the Auckland Open last month, which secured him a second career title.
In the other semi-final, world number one Carlos Alcaraz will compete against defending champion Andrey Rublev. Alcaraz secured his place in the last four with a resilient win, while Rublev as well advanced through his quarter-final tie.
