Novak Djokovic has been knocked out of the Dubai Tennis Championships, falling in straight sets 6-4 7-6(4) to Czech Republic's Jiri Vesely.
Vesely, who had to battle through qualifying to reach the quarter-finals stage, beat Djokovic in one hour and 59 minutes to progress to the semis.
The result means Daniil Medvedev will be the new world number one from next week and Vesely believes it will be refreshing to see a new name at the top of the ATP rankings.
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Vesely said on-court afterwards: "After yesterday's match I was joking that I did not want to fail my record against Novak because I was leading. I never expected to lead again.
"It's great for tennis to have somebody new at world number one again.
"We all know Novak missed the Australian Open but he's such a champion. He's been world number one for 361 weeks.
"Tennis needs new number ones and new generations coming through, I think it's just great."
Backed by strong Czech support, Vesely took the first set as he sought a repeat of his victory over Djokovic in Monte Carlo in 2016.
In the first meeting between the two since then, Vesely got off to a fast start, breaking the Djokovic serve in the opening game.
Djokovic battled back to level at 2-2 but Vesely, who went after the Serb's second serve all the time, restored his break advantage in seventh game and held his serve to take the opening set in 48 minutes.
The second set was equally impressive from Vesely who broke the world number one's serve to go 4-3 up.
Vesely's confidence was flowing and he produced a delightful shot through his legs before going 30-0 up on his service game before rescuing a break point to go 5-3 up.
The left-hander had the chance to serve for the match but Djokovic wore his opponent down to level the score at 5-5, converting his third break point of the game.
The pair went to a tie-break and it was Vesely who emerged victorious, sealing it with a crushing forehand winner.
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22/02/2022 AT 13:02