Defending champion Alexei Popyrin rallied from a set down to beat world No 9 Holger Rune 4-6, 6-2, 6-3 and reach the National Bank Open quarter-finals.
The Australian will put his growing reputation as one of the biggest giant-killers on the tour to the test when he faces Alexander Zverev in the last eight, after the top seed benefited from Argentina’s Francisco Cerundolo withdrawal while the German was leading 6-4, 1-0.
Popyrin started strongly against Rune but was unable to make the most of his early touch as he failed to close out 11 break points while the fifth-seeded Dane took the first set.
The 25-year-old recovered to convert two breaks while only giving up a pair of unforced errors during a powerful second set before easing through the third on Saturday night.
“I started this week not high on confidence, needing to get a grasp of the mental side,” Popyrin said. “But this week I kind of just let go of all the pressure.”
“After the first set I was pissed. But when I came back out to return again, it felt like I was in control of the match. I told myself to be aggressive on the next break point that I got, and from then on I felt quite comfortable.”
Popyrin has now won seven of his past nine matches against players ranked in the top 10 across a 12-month stretch of form that began while on the way to claiming the Canadian ATP Masters 1000 last year.
The 18th seed has also extended his winning streak in Canada to nine matches before his quarter-final showdown with the world No 3.
Zverev is the top seed in Toronto with top-ranked Jannik Sinner – the 2023 winner – and No 2 Carlos Alcaraz skipping the hard-court event.
“I feel comfortable on these courts, where I hit my first aggressive shot and then can dictate from there” Popyrin said. “My forehand was the standout today.”
Alex Michelsen is through to the quarter-finals after defeating fellow American Learner Tien 6-3, 6-3. Michelsen will face 11th seed Karen Khachanov after the Russian beat eighth-seeded Casper Ruud of Norway 6-4, 7-5.
Alex de Minaur will take on seventh seed Frances Tiafoe with a quarter-final spot up for grabs, after Christopher O’Connell pulled out of their all-Australian third round clash due to an abdominal injury.
