TORONTO, Canada - Karolina Pliskova's tenure as World No.1 began with a flourish on Wednesday in Toronto, as the top seed ousted Anastasia Pavlyuchenkova in her first match at the Rogers Cup, 6-3, 6-3.

In her first singles match officially at the top of the world rankings, Pliskova improved her head-to-head against the Russian to 5-0 overall, and has not lost a set in those five career meetings. 

"[I had a little bit of nerves] before the match, but during the match I felt much better, especially at the end," the Czech said on-court. "I played doubles yesterday so the nerves went out a little bit yesterday, and I felt good today. I'm definitely happy that I'm through to the next round."

Pliskova struck 16 winners and 12 unforced errors in what was a tidy match for her off the ground, and broke the Pavlyuchenkova serve seven times in nine opportunities.

Though Pliskova's usually fearsome serve was not firing on all cylinders - as she served 46% for the match - she nonetheless saved five of the nine break points she faced in the 70-minute victory.

"I knew that I have good record against her, but it's a while what we've been playing the last match," Pliskova assessed after the victory. "I didn't play a match since Wimbledon - after a while back on hard court, so I was not really expecting good tennis, and it was not good tennis.

"I'm happy to be back even though the match was not the best, but I think it's first after a while. It can be better in a few more, let's say, matches or in a few more days. I had good practice time, so it's been two, three weeks when I'm playing on hard now, but still it's different in practices and matches."

Wednesday's victory was not Pliskova's first of the week, as she partnered Eugenie Bouchard to a first-round doubles victory on Tuesday against Dominika Cibulkova and Kirsten Flipkens - a fact she admitted helped her settle in ahead of her first singles match.

"I was looking for somebody because originally I was supposed to play with my sister, but she got injured in China so she couldn't go, unfortunately," she said. "I was looking for somebody for doubles this week, and I saw [Bouchard]'s going to be on the list so I just asked her. I texted if she wants to play maybe a few matches of doubles, and she was for it.

"I have to say the doubles match yesterday I played with Eugenie kind of helped me that I already had a match. I felt okay on the court yesterday, so it was a good decision to play."

In the third round, Pliskova will next take on another big server in her own right, Japanese teenager Naomi Osaka, who defeated No.15 seed Anastasija Sevastova in straight sets, 6-3, 6-4.

After a successful debut at World No.1, Pliskova - who bowed out at that stage in Canada a year ago before going on a summer tear that helped her set the stage for her rise to the top of the rankings - is now keen to take things one step at a time.

"I still want to play my best tennis, and we will see how I will fight against the defending points," she said. "Obviously, we all know I won Cincinnati. I was in [the] final in New York. So it's going to be tough to play the same as I was playing last year, but I believe I'm on a good way and hopefully I can play closer to what I was playing last year here."