Top seed Daniil Medvedev was two points from defeat against Poland's Hubert Hurkacz, but he held his nerve to produce a fine 2-6, 7-6(6), 7-6(5) comeback to reach the National Bank Open semi-finals on Friday evening.
The Russian will take on John Isner of the US, who extended his win streak to nine matches after he halted Frenchman Gael Monfils 7-6(5), 6-4 to reach the last-four.
Medvedev is seeking his fourth ATP Masters 1000 title, and a 12th tour-level title overall.
Medvedev, whose Wimbledon campaign was cut short in the fourth round by the seventh-seeded Hurkacz just over a month ago, was out for revenge as they faced off for the second time on the ATP tour. The Russian fired 38 winners, including 23 aces, to find a way to victory against Hurkacz, who did not drop serve once in the contest.
"It was definitely not easy. He was on top of me. But to win matches like this gives you a huge boost of confidence. It's a pleasure to be standing here and giving interviews."
"He had his chances and he was probably the better player for at least two sets for sure, but that's tennis," Medvedev told atptour.com. "We both have great serves and I managed to hit some aces when I needed to."
Third seed Stefanos Tsitsipas' season continued to go from strength to strength as the Greek recorded a 45th tour-leading victory of the year to defeat Casper Ruud of Norway 6-1, 6-4 to reach the semi-finals.
The 23-year-old, who rose to a career-high No. 3 in the ATP rankings earlier this week, served well throughout and hit the ball with great power and depth to advance to his seventh ATP Masters 1000 semifinal in 74 minutes.
Tsitsipas will next face Reilly Opelka after the American defeated Spaniard Roberto Bautista Agut as the Greek tries to advance to the championship match in Canada again.
Camila Giorgi Enters Semis With Win Over Coco Gauff
Camila Giorgi avenged a recent loss to American teenager Coco Gauff as the Italian upset the 15th seed to enter the semi-finals of the National Bank Open on Saturday (IST).
In the last-four, she will face Jessica Pegula of the US, who won a tight contest against No.13 seed Ons Jabeur of Tunisia.
Camila defeated the No.15 seed Coco, 6-4, 7-6(2), in their quarter-final clash.
"I think it was a great match," Camila was quoted as saying by wtatennis.com. "I think I was very consistent. It was a great level, I think."
It took an hour and 39 minutes for former top-30 player Camila to oust the American teenager, extending her career-best performance in Canada. Camila had never reached the round of 16 at this event prior to this season.
World No.71 Camila has now eliminated three top-25 players from the Montreal event this week. The Italian upset No. 9 seed Elise Mertens of Belgium in the first round and No.7 seed Petra Kvitova of the Czech Republic in the round of 16.
Coco had defeated Giorgi in straight sets in their only previous meeting, which came during the American's run to the title on the clay courts of Parma earlier this year, in Camila's home country.
However, Camila turned the tables on the Canadian hardcourts, winning 62 per cent of points off of Coco's second serve, which led to four breaks over two close sets.
"I think it's the first time I don't have interruption," Camila said of her strong form. "I play many, many tournaments now in this year without stopping. So I think this is the key. I didn't have [this] in other years. I think I always had some issue physically, or injury or something. So I think now I'm playing my game really."
Next up for Camila will be a semifinal clash against Jessica Pegula of the US, who staged a fine comeback to overcome No.13 seed Ons Jabeur of Tunisia, 1-6, 7-6(4), 6-0.
Jessica had already beaten Ons once in Canada, having knocked out the Tunisian in their first meeting, en route to her maiden WTA final at 2018 Quebec City.
World No. 1 Ashleigh Barty Set for Cincinnati Event
World No. 1 Ashleigh Barty of Australia is set to play her first tour event since her emotional victory at Wimbledon last month when she competes in the Western & Southern Open -- a WTA 1000 event in Cincinnati, Ohio -- that begins on Monday (16 August).
The Aussie fell in a tough first-round loss at the Tokyo Olympic Games against Spain's Sara Sorribes Tormo but walked away from her Olympic debut with a bronze in mixed doubles.
Ashleigh leads the top quarter and will face a qualifier in the second round. She could face defending champion Victoria Azarenka of Belarus in the Round of 16, with a trio of major champions looming as a potential quarterfinal opponent: Barbora Krejcikova (Czech), Garbine Muguruza (Spain) and Sloane Stephens (US). In fact, if Sloane gets past her qualifier opponent in the opening round, she could face Garbine in the second.
French Open champion Barbora Krejcikova will play her first-round match against San Jose finalist Daria Kasatkina of Russia. The Czech has won 22 of her past 24 matches.
No.2 Naomi Osaka of Japan, who made her return to the court at the Olympics late last month for the first time since withdrawing from the French Open in May, anchors the fourth quarter, along with No.7 seed Bianca Andreescu of Canada, who is making her Cincinnati main-draw debut.
With a bye into the second round, Naomi could face 17-year-old Coco Gauff in the second round. The young American made her seventh quarterfinal of the season in Montreal this week. To earn a third meeting with Naomi, Coco will have to defeat a qualifier in the first round.
The bottom quarter also features a rematch of the Tokyo 2020 gold medal match between Switzerland's Belinda Bencic and Marketa Vondrousova of the Czech Republic, which the former won 7-5, 2-6, 6-3 to become the first woman to win tennis gold for Switzerland.