Novak Djokovic has suffered a shock 6-4 7-6(4) defeat by qualifier Jiri Vesely in the Dubai Tennis Championships quarter-finals on Thursday and will lose his status as world No. 1 next week.
US Open champion Daniil Medvedev, who is currently playing in a tournament in Mexico, will move to the top of the rankings on Tuesday (NZ time).
It was the 34-year-old Djokovic's first tournament since being deported from Australia last month for not being vaccinated against COVID-19, preventing him from being able to defend his Australian Open title.
Russian Medvedev will become the first player other than Djokovic, Roger Federer, Rafa Nadal or Andy Murray to top the rankings since February 1, 2004.
Djokovic spent a record 361 weeks atop the rankings and won eight tour-level titles, including three Grand Slams, since regaining his top-ranked status in February, 2020.
"Unfortunately, it wasn't my day," Djokovic said. "I congratulate Jiri. He played better. He just went for his shots. His serve was big. His whole game was big.
"I expected myself to play on a higher level, for sure. I mean, I can do better. But credit to Jiri."
Playing in his first event since being deported from Australia ahead of the year's first Grand Slam tournament, Djokovic lost serve in the opening game as Vesely matched him stroke for stroke.
Djokovic broke back at 1-2 but was never allowed to settle by Vesely, whose clever drop shots had his opponent scrambling at the net as the Czech sealed the first set 6-4.
The 20-times major winner started strongly in the second set but Vesely maintained his high level, racing into an early lead in the tiebreak to clinch his second career victory over Djokovic.
Elsewhere at Dubai, Kiwi Michael Venus and doubles partner Tim Putz advanced to the semi-final stage, with a three-set win over Frenchman Fabrice Martin and Andrey Golubev.
The two pairs went deep into the third set, before Venus and Putz prevailed 4-6 6-3 10-4.
On Saturday morning (NZ time), they'll face American Austin Krajicek and France's Édouard Roger-Vasselin for a place in the final.
Reuters/Newshub.
