Czech qualifier Jakub Mensik delivered a major upset at the Qatar Open, defeating world number two Jannik Sinner 7-6 (7-3) 2-6 6-3 in the quarter-finals. The 20-year-old's victory ended Sinner's impressive run of 22 wins from 23 matches, with his only previous loss coming against Novak Djokovic at the Australian Open semi-finals.

Mensik's triumph sets up a semi-final clash with unseeded Arthur Fils, who beat fellow Czech Jiri Lehecka 6-3 6-3. Meanwhile, Carlos Alcaraz advanced to face defending champion Andrey Rublev after defeating Karen Khachanov 6-7 (3-7) 6-4 6-3. Alcaraz, who won the Australian Open to complete a career Grand Slam, extended his winning streak to 10 matches.

In doubles, British pair Julian Cash and Lloyd Glasspool reached the final, defeating French duo Quentin Halys and Pierre-Hugues Herbert 6-2 6-3. They'll face compatriots Henry Patten and Harri Heliovaara in a repeat of last year's final. The Qatar Open continues to deliver surprises as lower-ranked players challenge established stars.