Doha-Two-time champion Andy Murray secured his spot in the semifinal with a comeback 4-6, 6-1, 6-2 win against Alexandre Muller in two hours and four minutes to set up a clash with Jiri Lehecka, who earned the biggest win of his career after the upset of world No. 5 and the tournament's top seed Andrey Rublev 4-6, 6-4, 6-3 in the first match of the day.
Murray, ranked 70, reached the last-four less than 24 hours after coming off a three-hour battle with the tournament's fourth seed, Alexander Zverev, in the round of 16, and the three-time Grand Slam winner is just two matches away from equaling Roger Federer’s record of three-time champion in Doha.
Murray's next opponent, the 21-year-old Lehecka (ranked 52), broke twice to seal his victory after one hour and 41 minutes, thereby improving his ATP Head2Head series against Rublev, the 2020 winner, to 1-1.
Meanwhile, Daniil Medvedev, the third seed, survived Christopher O’Connell's resilience to book his semifinal clash against Felix Auger-Aliassime, the world No. 9, who edged out Alejandro Davidovich Fokina, the seventh-seed, in straight sets, 6-4, 7-6(5).
The world No. 8 posted a 6-2, 4-6, 7-5 win in one hour, 59 minutes to extend his head-to-head advantage against O’Connell to 2-0, following his 2020 US Open Round of 64 victory.
Medvedev, who is appearing in Doha for the first time, defeated Liam Broady in straight sets in his opening match, while second-seeded Felix Auger-Aliassime staged a 4-6, 6-1, 6-4 comeback victory against Jason Kubler.