Montreal's Felix Auger-Aliassime picked up his second win over a top-25 player this season with a 7-6 (2), 5-7, 6-4 win over South Korea's Hyeon Chung on Wednesday at the Chengdu Open.
The 18-year-old Auger-Aliassime, a lucky loser in Chengdu, had 11 aces and converted three of 10 break point opportunities against Chung, ranked 23rd in the world and seeded second at the Chinese tournament.
Auger-Aliassime will face Australia's Bernard Tomic in the quarterfinals.
Auger-Aliassime is playing in his first tournament since retiring from his first-round match at the U.S. Open against fellow Canadian Denis Shapovalov with an accelerated heart rate.
The Canadian teen, ranked 147th on the ATP Tour, turned heads earlier this year with a win over No. 18 Lucas Pouille in the first round of the Rogers Cup in Toronto.
In other results in Chengdu, Portugal's Joao Sousa beat Vancouver's Vasek Pospisil 6-7 (4), 6-4, 7-6 (0).
Meanwhile, in Shenzhen, China, Japanese qualifier Yoshihito Nishioka upset Shapovalov 7-6 (5), 3-6, 7-5. Shapovalov, from Richmond Hill, Ont., was seeded sixth.
The Canadian Press
