Denis Shapovalov put up a near-perfect serving performance to beat Steve Johnson 6-3, 7-6 (3) at the Japan Open on Wednesday.
The No. 7 seed Canadian conceded only one point on his first serve and had 11 aces. Shapovalov, who lost in the semifinals four years ago, will next take on Japanese qualifier Rio Noguchi for a place in the quarterfinals.
"[This was] definitely one of my best serving matches," Shapovalov said. "I kind of felt like I needed to against Steve ... I'm very happy with my serving performance today and hopefully I can keep it up throughout the week."
World No. 11 Taylor Fritz beat Australia's James Duckworth to advance to the final 16 of the competition.
Fritz won 6-2, 6-7 (2), 6-1 to set up a tie with Hiroki Moriya.
Also, Miomir Kecmanovic came back to beat Yoshihito Nishioka 2-6, 7-6 (1), 6-2, and Kwon Soon-woo defeated Mackenzie McDonald 6-3, 6-7 (4), 6-2.
Elsewhere, Spain's Pedro Martinez edged compatriot Jaume Munar 4-6, 6-3, 6-1 in two hours and 38 minutes to advance.