The Australian has now won seven of his last nine matches against Top 10 players, a stretch that began in Canada a year ago, where—in Montreal—he made a surprise run to his first Masters 1000 title.

Defending champion Alexei Popyrin of Australia beat fifth-seeded Holger Rune of Denmark 4-6, 6-2, 6-3 on Saturday night to reach the National Bank Open quarterfinals.

Alex Michelsen of the United States also reached the quarters with a 6-3, 6-3 victory over countryman Learner Tien at the ATP ...