A 45-minute rain interruption did little to stop the progress of Rafael Nadal at the Toronto Masters as he defeated Stan Wawrinka 7-5, 7-6 (7/4) to reach the quarterfinals.
The halt in proceedings came 63 minutes into the opening set, after Wawrinka saved a Nadal set point for 5-all, with the Spaniard then holding serve for 6-5.
When the weather passed, the pair returned, with Nadal wrapping up the set on his second chance.
The second set was a battle as the Swiss, a three-time Grand Slam champion, fought back from an early break down to take a 2-1 lead. The pair again trading breaks in the fifth and tenth games.
Nadal came from a mini-break down in the tiebreaker and secured victory on his second match point.
Second seed Alexander Zverev, the holder, lined up a re-run of last week's Washington semi-final as he again takes on Stefanos Tsitsipas.
The Greek, who turns 20 on Sunday, knocked out his second seed in as many matches, stunning Wimbledon champion Novak Djokovic 6-3, 6-7 (5/7), 6-3 to reach the quarterfinals.
Zverev rolled over Russian Daniil Medvedev 6-3, 6-2 in 52 minutes while never facing a break point.
Tsitsipas called his knockout of Djokovic the best match of his career.
The number 27 will play the first Masters 1000 quarterfinal of his career.
"He played very well and deserved to win without a doubt," Djokovic said. "I just played not that great.
"I didn't return well. It wasn't that great of a match."
Bulgarian fifth seed Grigor Dimitrov laboured for almost two and a half hours to subdue Frances Tiafoe of the United States 7-6 (7/1), 3-6, 7-6 (7/4).
He next faces Wimbledon runner-up and fourth seed Kevin Anderson who defeated Ilya Ivashka of Belarus 7-5, 6-3 to also make the last-eight.
Sixth seed Marin Cilic continued his quiet progress, beating Argentine 11th seed Diego Schwartzman 6-3, 6-2.
Halep drubs Venus
World number one Simona Halep crushed seven-time Grand Slam winner Venus Williams in straight sets at the WTA Montreal event just hours after a delivering a marathon three-hour victory over Anastasia Pavlyuchenkova.
Top seed Halep took no prisoners against Venus, blitzing the 38-year-old American 6-2, 6-2 in just 71 minutes to reach the quarterfinals.
Halep next faces number six seed Caroline Garcia, who overwhelmed former World No 1 Maria Sharapova hours earlier.
Aryna Sabalenka staged one of the biggest wins of her career, saving three match points en route to a 5-7, 6-2, 7-6 (7/4) upset of second seed Caroline Wozniacki.
US Open champion Sloane Stephens reached the quarterfinals with a rollercoaster 6-2, 7-5 win over Spain's Carla Suarez Navarro.
Britain's Johanna Konta saw off two-time Grand Slam champion and former world number one Victoria Azarenka, 6-3, 6-1.