TORONTO — This time last year, Greek teenager Stefanos Tsitsipas had yet to record a victory on the ATP World Tour.
His breakthrough season reached another level Thursday when he stunned one of the sport's biggest stars.
Tsitsipas upset Novak Djokovic 6-3, 6-7 (5), 6-3 in third-round play at the Rogers Cup in a thrilling battle between one of the Tour's top young guns and the reigning Wimbledon champion.
The 19-year-old Tsitsipas broke the ninth-seeded Serb early in the third set and held serve from there to reach his first career Masters 1000 quarterfinal.
"I was waiting and I grabbed him like a bulldog and I stuck there," Tsitsipas said. "I executed my plan, I knew at some point that he was going to break. I just patiently waited for the moment and it happened."
Djokovic faded late against his flashy opponent, who played with poise and power on a warm, breezy afternoon at Aviva Centre.
Tsitsipas set up match point with a scorching crosscourt winner before completing the victory in their first career meeting in two hours 17 minutes.
"I thought Tsitsipas played very well and he deserved to win without a doubt," Djokovic said. "But I just played not that great, especially from the baseline.
"I didn't return well. So just all in all, it wasn't that great of a match."
Earlier, fifth-seeded Bulgarian Grigor Dimitrov outlasted American Frances Tiafoe 7-6 (1), 3-6, 7-6 (4) and fourth-seeded South African Kevin Anderson topped qualifier Ilya Ivashka of Belarus 7-5, 6-3.
Denis Shapovalov of Richmond Hill, Ont., — the only Canadian player remaining in the tournament — was to face Robin Haase of the Netherlands on Thursday evening.
In the other late matches, top-seeded Rafael Nadal of Spain beat Swiss wild-card entry Stan Wawrinka 7-5, 7-6 (4) and eighth-seeded American John Isner was upset by Russia's Karen Khachanov 7-6 (5), 7-6 (0).
"Very positive victory for me against a very tough opponent," said Nadal. "That's what I needed, a match like this to be a little more confident. Just happy to be in the quarterfinals already."
Djokovic, a four-time Rogers Cup champion and former world No. 1, returned to the top 10 in mid-July after missing several months due to a right elbow injury.
His trademark retrieving skills were on display throughout the match but Tsitsipas used strong groundstrokes to push the pace and force Djokovic to fully stretch on several rallies.
The aggressive play led to defensive shots from his opponent and Tsitsipas often converted when he had chance.
He took advantage of a Djokovic unforced error for an early break at 4-2 and used a few 210-km/h serves to take the first set by holding at love.
Tsitsipas let a double-break point opportunity slip at 4-4 in the second set, eventually giving up the game after back-to-back shanks.
Djokovic went up a mini-break early in the tiebreaker but two straight challenges would go Tsitsipas' way, each time by a whisker. However, the 31-year-old Serb converted his third set point.
With his long dark locks flowing behind a bright pink headband, Tsitsipas didn't seemed fazed.
He held serve to open the set and wrong-footed Djokovic after the veteran served at deuce, setting up an overhead smash for the advantage before a brilliant backhand winner secured a 2-0 lead.
"I was serving well so that break was everything," Tsitsipas said. "It gave me the win at the end."
Djokovic, a 13-time Grand Slam champion, couldn't claw back and eventually seemed resigned to the result, even smiling a few times in the final game.
"I remained tough," Tsitsipas said. "I didn't crack under pressure. I was brave. I played exactly how I had to play at that moment."
Tsitsipas raised his arms and tossed his racket in the air after sealing the win. He'll next face second-seeded defending champion Alexander Zverev of Germany, a 6-3, 6-2 winner over Russia's Daniil Medvedev.
Djokovic had a quick break before returning to the doubles court with Anderson. They beat French duo Pierre-Hugues Herbert and Nicolas Mahut 4-6, 6-4, 10-7.
Tsitsipas was ranked 168th in the world a year ago but has since rocketed to No. 27. The six-foot-four right-hander has reached the quarterfinals at seven Tour events and was a finalist at the Barcelona Open last April.
He defeated seventh-seeded Dominic Thiem of Australia earlier this week and will be looking to avenge a semifinal loss to Zverev last week in Washington.
Play continues through Sunday at the US$5.94-million tournament on the York University campus.
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Gregory Strong, The Canadian Press