Karen Khachanov uses serve to slay Casper Ruud in Toronto

No. 11 seed Karen Khachanov won 29 of 30 first-serve points (96.7 percent) en route to a 6-4, 7-5 victory over No. 8 Casper Ruud on Saturday to reach the quarterfinals of the National Bank Open at Toronto.

The Russian had seven aces among 29 winners while dispatching Ruud to reach the 10th 1000-level quarterfinal of his career.

"My game plan was working, especially with the first serves," Khachanov said. "The first serves in was not a high percentage, but the points won was quite high.

"I guess (there were) a little bit of nerves. It became difficult but I'm super glad I was able to pull through, break him one more time and finish the match."

Ruud of Norway had 23 winners, including nine aces.

Khachanov will next face 26th-seeded Alex Michelsen, who recorded a 6-3, 6-3 victory over fellow American Learner Tien to reach the quarters.

Michelsen won 72.2 percent of his first-serve points (26 of 36) while beating his close friend.

It also helped that Tien committed 20 unforced errors.

"It feels really good, it's uncharted territory from this point on," Michelsen said. "We're very close friends, we've been texting and sending each other memes as normal. We've grown a lot together."

Top-seeded Alexander Zverev of Germany will face No. 14 Francisco Cerundolo in the night session. No. 5 Holger Rune of Denmark meets No. 18 Alexei Popyrin of Australia.

--Field Level Media