Australia's Alexei Popyrin on Monday registered the third Top-10 win of his career, beating World No. 6 Felix Auger-Aliassime of Canada 6-4, 7-6(5) to progress to the second round of the Adelaide International 1.
The World No. 120, who has also earned victories against Dominic Thiem and Stefanos Tsitsipas, will next face American Marcos Giron.
Popyrin struck 11 aces and rallied from 1-4 in the second set, holding his nerve in the second-set tie-break to advance after one hour and 53 minutes in his first ATP Head2Head meeting against Auger-Aliassime.
"I would say so. Yeah, for me, obviously he's one of the in-form players that we have on the tour right now," Popyrin said after the match. "So yeah, if we go by ranking and by performance, then yeah, it's probably one of the better wins of my career."
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"A really good win for me, especially coming off last season where I only had five wins on the circuit," ATP Tour quoted Popyrin saying. "For me it's a very, very important win. I know I have the level to play against guys like that, and today just proved it. I'm happy. I'm not surprised, to be honest, but I'm happy with it."
Felix, who held a 60-27 record in 2022, winning four tour-level titles, however, was unable to find his best level, misfiring at key moments in his first match of the year.
In other matches, Holger Rune too suffered a first-round exit, falling against Japan's Yoshihito Nishioka.
The 27-year-old Japanese, currently at a career-high No. 36 in the ATP Rankings, rallied to upset the fifth seed 2-6, 6-4, 6-4 in two hours and seven minutes.
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Nishioka will next take on American Mackenzie McDonald.
Rune, who was making his second appearance at the ATP 250 event, had a standout 2022 season. He won his maiden ATP Masters 1000 title in Paris and cracked the Top 10 of the ATP Rankings for the first time.
Miomir Kecmanovic of Serbia started the new year with a win, overcoming Australian Christopher O'Connell 6-4, 6-4.
The Serbian could play Daniil Medvedev, who begins his campaign against Italian Lorenzo Sonego, in the second round.
