A subdued Carlos Alcaraz has been knocked out of the Astana Open after a 7-5 6-3 defeat to David Goffin.
The world No.1's pursuit of a seventh ATP singles title this season came to an abrupt end in the opening round in Kazakhstan as Goffin's precise, measured performance saw the Belgian over the line in one hour and 48 minutes.
Goffin will play Adrian Mannarino in the second round after he beat wild card Stanislas Wawrinka 1-6 6-2 6-3.
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"I always believe that I have the level to cause some trouble against those guys," Goffin said.
"Of course it has not been my best period, I haven't been playing really well in the past few tournaments, but I always believe and practice and you never know.
"When you play against the world No. 1 on a big stage, big crowd, the fire inside gives you so much power to play your best tennis because you don't have any choice. You have to fight and give your best and that was the case today. I always believed I had it and I am happy you can still do it there."
Goffin, who entered the first round as a lucky loser, fought back from a break down in the third game in the opening set by breaking the US Open champion in his next two service games.
Alcaraz produced an emphatic love break to get the scores back on 5-5, but Goffin converted his first set point on the 19-year-old's serve to win it 7-5.
Momentum was firmly with the Belgian and he raced in front in the second set, reeling off the opening three games.
Alcaraz fought off two break points to get on the scoreboard and make it 3-1, but Goffin quickly found his stride again and held his nerve to see out his remaining service games to produce his finest win in 2022.

Highlights: Tsitsipas eases past Kukushkin to reach second round of Astana Open

Stefanos Tsitsipas is through to the second round in Astana after a straightforward 6-3 6-4 win over Mikhail Kukushkin.
Tsitsipas, who has won titles in Monte Carlo and Mallorca this year, overpowered the Kazakh wild card and advanced through after 83 minutes to record his 50th tour win this year.
The third seed is bidding to win his first ATP 500 tournament. He has reached eight ATP 500 finals in his career, but has lost all of them.
Meanwhile, Nick Kyrgios is through to the quarter-final of the Japan Open following a 6-3 6-1 victory against Chun-Hsin Tseng in Tokyo's Ariake Colosseum.
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