TORONTO -- Bianca Andreescu grew increasingly frustrated as her injured right shoulder forced her to sit out tournament after tournament for a large stretch of her breakout season.

Turns out that time off may have done more to help than hinder the Canadian rising tennis star.

Andreescu, competing in just her fourth match since May, advanced to the quarterfinals of the Rogers Cup on Thursday by edging world No. 5 Kiki Bertens of the Netherlands 6-1, 6-7, 6-4 in dramatic fashion on centre court.

"Being off for that long and coming into the Rogers Cup and getting into the quarterfinals means so much to me," the 19-year-old Andreescu said.

"And this time off actually helped me -- I figured a lot of things out -- and it's showing on court."

Andreescu won 82 per cent of her first-service points, converted on 5-of-13 break points and saved 7-of-9.

She capitalized on her fourth match point when Bertens hit a second straight double fault to end the afternoon tilt, which was delayed one hour 11 minutes by rain at Aviva Centre.

Andreescu will face former world No. 1 Karolina Pliskova of the Czech Republic in the quarterfinals Friday.

The Mississauga, Ont., native had played nearly five hours of tennis over the first two days of the tournament, needing three sets to defeat Daria Kasatkina on Wednesday night, and three against fellow Canadian Eugenie Bouchard in the first round Tuesday.

She fell behind by a set against Bouchard, then faced a 5-3 deficit in the third set against Kasatkina, but she rallied by winning four straight games to advance to the third round.

"This is a pretty damn good performance I've been putting up right now," Andreescu said. "I wasn't expecting it, really. I had zero expectations going into this. I was just really happy to be back on court.

"But I can't complain right now, so maybe I should just have zero expectations and everything will be fine."

Andreescu is the fifth Canadian woman to make it to the quarterfinals of the Rogers Cup since it became a hardcourt event in 1979, and the first to do it since Aleksandra Wozniak in 2012.

She was on fire early on against Bertens, earning a big break to go up 5-1 in the first set and screaming into the crowd after her winning point.

The 19-year-old started slowly in the second set, falling behind 0-3. But she saved four break points to tie it 3-all, then dug out of a second straight 0-40 hole to hold at 4-all. Bertens had her own comeback in the tiebreak, rallying from a 5-2 deficit to take it 9-7.

Bertens said Andreescu was playing an aggressive game.

"She was putting (on) a lot of pressure," she said. "And yeah, she can do everything with the ball. So she made it tough today."

"She's a really good player," Bertens added. "So it was really not a surprise for me."

The win puts Andreescu at 5-0 against top-10 ranked opponents this year -- including her Indian Wells final win over then-No. 8 Angelique Kerber in March for her first WTA title.

She also improved to 14-3 in three-setters this year, and 24-4 on the season overall.

Andreescu, who began the year outside the top 100 before skyrocketing to her current position at No. 27, said she wants to improve that ranking before the season is out.

"I would say my goals for the end of the year would have to be to break the top 10," she said.

"I really believe that I can do that."

Pliskova, meanwhile, downed No. 16-seed Anett Kontaveit of Estonia 6-3, 7-5 in Thursday's first match on centre court.

She will face Andreescu for the first time Friday.

"I just saw her a little bit on TV. So it would be interesting, of course challenging, to play her here in Canada," Pliskova said.

Pliskova has a lot at stake at this Rogers Cup, with a chance at reclaiming the top spot on the WTA rankings with a solid run at the Premier 5 event.

Pliskova also reached the quarterfinals of the Rogers Cup the last time it was in Toronto in 2017, during her seven-week run as the top-ranked player in the world. She lost to Bertens in the second round of last year's tournament in Montreal.

Andreescu praised Pliskova's serve, and said facing Bertens was a good warmup to her quarterfinal matchup.

"I'm going to study her, study where she likes to serve to, just so I can be ready for those return games because every point is important," she said. "I'm trying to get as much as I can."

In other early play Thursday, American Sofia Kenin continued her stellar run at the tournament with a 6-2, 6-2 win over Ukrainian teenager Dayana Yastremska.

Kenin, ranked No. 29, had knocked off the top-ranked Ashleigh Barty on Tuesday to reach the third round. She will play 2017 Rogers Cup champ Elina Svitolina in the quarterfinals.

Svitolina, from Ukraine, defeated 2015 tournament winner Belinda Bencic of Switzerland 6-2, 6-4 in another rain-interrupted match on the grand stand.

Wimbledon champion Simona Halep of Romania, the 2018 Rogers Cup winner, beat Svetlana Kuznetsova of Russia 6-2, 6-1 later Thursday.

Also Thursday, American star Serena Williams took on Russian Ekaterina Alexandrova and Latvian Jelena Ostapenko played qualifier Marie Bouzkova of the Czech Republic.

No. 2 Naomi Osaka of Japan was slated for the late match against qualifier Iga Swiatek. Swiatek upset former No. 1 Caroline Wozniacki in three sets Wednesday night.