MONTREAL, Canada - No.14 seed Elise Mertens had to come back from a set down and save match point against Aryna Sabalenka, but she completed the turnaround to book her spot into the Coupe Rogers quarterfinals.

Sabalenka finished a tough rain-delayed match against Wozniacki earlier today, where she fired a mind boggling 64 winners to come back from a set down and edge through a marathon two hour and 33 minute battle.

As a result she had only 90 minutes to turn around and get ready for her third round against Mertens - and the fatigue was evident as the match wore on, the Belgian winning 2-6, 7-6(1), 6-0 after two hours and 12 minutes.

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“It was a long wait today which was tough,” Mertens said of the weather-delayed match. “I tried to rest, have a bit of food and keep myself energized. It’s hard when you don’t know who you’re playing until a few hours before, but of course I’ve played her before so that made it a bit easier.

“It was a great performance from her in the first set - I felt like I just kept on fighting in every point, and I won the match at the end.”

Sabalenka was in a hurry in the one-sided opening set, saving six break points and keeping her opponent under pressure throughout with her powerful forehands. She bracketed the set with a break to start and another to finish as she took the opener in 38 minutes.

She was knocked off her rhythm a bit as the second set was halted due to a passing rain shower. Mertens took advantage to grab her first break of the match and get ahead 2-0, but it was short-lived as Sabalenka found her big returns once more to level the score at 2-2.

The pair wrestled for the momentum in the tense few games to follow, but as the set wound down it was Mertens who raised her level. She weathered Sabalenka’s power game and dodged a match point at 5-4 to send them into a tiebreaker. Mertens owned more of the longer rallies as errors started to creep into the Belarusian’s game, taking the tiebreak 7-1 to force a decider.

With already so much tennis under her belt today, Sabalenka’s fatigue became more evident in the final set, and Mertens took advantage to run her opponent all over the court. She reeled off the next six games in a row to break three times and seal the victory.

“I still remember that match point, it was on the line!” Mertens said. “She’s a great player, she can play these aggressive strokes so I tried to play even more aggressive and take the momentum earlier.”

Up next in the quarterfinals, Mertens will take on the No.5 seed Elina Svitolina. Svitolina took down Johanna Konta in straight sets, 6-3, 6-4 earlier in the day.

“I’m really happy with the way I’m playing, I feel like my game is improving and I’m getting a good rhythm. I’ve played Svitolina two times already, she’s a great player with great defense - I just have to play my game and go point by point, same as today.”