Venus Williams and Angelique Kerber play the match of the tournament at the Rogers Cup in Montreal

MONTREAL – In her first-ever visit to the Rogers Cup in Montreal over a 20-year career, Venus Williams is turning back the clock.

The 33-year-old American posted an impressive 6-3, 3-6, 6-4 win over No. 6 seed Angelique Kerber of Germany Thursday night that electrified the crowd and brought out the best in both players, whose stark differences made it a high-voltage chess match between unrelenting offence and dogged defence.

You could call it a battle of good versus evil, then decide which of the two was your good and which was your evil.

Kerber was 3-1 against Williams going in. They hadn't met in nearly two years but their last two matches, at the Olympics in London and the U.S. Open, were wars of attrition.

"It's fun when you win those points. When you lose those, it's anguish. It's like, What else can I do? I think it was a match point, where I had her completely off the court. She hit such a great shot. I managed to miss it long. You think, Wow, what else can I do?" Williams said. "You just have to keep trying. That's the key playing against her. That's what she's done so well against me. She probably feels the same way. You just have to keep trying."

The match had plenty of points like this one, which came at the very end of the two hour, 25-minute display.

There were 35 break-point opportunities and 11 breaks of serve in all. Yet somehow it didn't at all feel like one of those women's matches, where the players struggle to hold and the eye rolling begin. It was too good for that. Williams still possesses one of the most dangerous, if erratic serves in the game and Kerber, well, does not. But each point was a high-quality entity all on its own.

Williams felt her serve let her down, and that leveled the playing field. In one game, she hit four double-faults, so it's hard to disagree with her. On the other side, Kerber's effort and body language were miles removed from the way she looked at times against Venus's sister Serena in the Stanford final just a few days ago.

She was engaged, and committed. Williams needed to rely a little more on defence because of her first-serve woes; Kerber had to step it up and be more aggressive than she's normally comfortable with, because she knew good defence probably wouldn't be enough.

"I think even in the second set she started to pick her game up. She was gaining momentum. She kept that momentum going through the second. I tried to keep it competitive even though I was down a couple breaks. It's not always easy to really kind of get your hands around a match when you're playing her," Williams said. "In the end, it was unbelievably competitive points from both of us. We've always played so competitively. So many matches I've been on the short end of the stick. It felt good this time to pull one out."

It's been many, many years since you looked to see if the Williams sisters fell in opposite halves of the draw, the way so many did for years with Roger Federer and Rafael Nadal.

With so many of the other contenders falling by the wayside in Montreal, now's the time.

Venus and Serena are in the same half; Serena plays Caroline Wozniacki today, while Venus takes on Carla Suárez Navarro, who upset No. 4 seed Maria Sharapova. If they win, they would meet in the semi-finals on Saturday.

As always with Venus and her on-going battle with Sjogren's disease, every day is a new day. She may wake up full of energy, or lacking any, independently of the effort involved in her previous match.

On the other side of the draw, No. 8 Victoria Azarenka (who defeated qualifier Heather Watson 6-2, 6-4 late Thursday and despite a heavily-taped knee, seemed in pretty good form) and No. 3 Agnieszka Radwanska remain. Unfortunately, they play each other. That means that either Ekaterina Makarova or upstart qualifier Coco Vandeweghe will be a Rogers Cup semi-finalist this year.