Aryna Sabalenka won a battle of Belarus on Friday, denying compatriot Victoria Azarenka the chance to return to the top 10 with a 6-2, 6-4 victory at the WTA Montreal Masters.

Azarenka, a 32-year-old with two Australian Open titles to her credit, last ranked in the elite group five years ago before motherhood.

The quarter-final success for top seed Sabalenka took 82 minutes, with the big-serving winner adding seven aces to her season's WTA-leading total of 265.

"I'm really happy with this, it was a tough match," Sabalenka said. "She played well.

"The second set was a little tricky. I'm really happy that I came back (after trailing 4-2) and won it. I'm pleased with the level today."

Sabalenka has now won three of four matches against her compatriot, including their last in October, 2020 in Ostrava.

Azarenka played the Canadian semi-finals in 2010 and 2011.

Sabalenka was playing her eighth quarter-final of 2021, putting her in the joint lead in that statistical category with world number one Ashleigh Barty.

"There were a few points that really made a big difference," Azarenka said. "I had opportunities in the first set.

"But she was playing much stronger in the important moments. I didn't really quite take my chances. 

"Compared to other players, she's probably one  of the hardest hitting."

Sabalenka will next take on fourth seed Karolina Pliskova after the Czech defeated Sara Sorribes Tormo of Spain 6-4, 6-0. Pliskova stopped Sabalenka in their last meeting, a Wimbledon semi-final in July.

In the bottom half of the draw, 15th seed Coco Gauff saved two match points before falling to Italy's Camila Giorgi 6-4, 7-6 (7/2).

The win served as revenge for Giorgi, who lost at home to the American teenager in Parma this season.

Giorgi, ranked 71st, added Gauff to a victim's list this week which has included 12th seed Petra Kvitova and number 16 Elise Mertens.

"I'm playing very consistently this season," Giorgi said. "I've had a lot of tournaments without interruptions or injury.

"I've played through the season without stopping, I think that's the key."

Giorgi will meet Jessica Pegula after the Australian Open quarter-finalist rallied past 13th seed Ons Jabeur 1-6, 7-6 (7/4), 6-0 in 90 minutes with four breaks of the Tunisian's serve.