• Serena Williams beat Naomi Osaka for the first time in her career Friday.
  • Williams won in straight sets, 6-3, 6-4, to advance to the Rogers Cup semifinal in Toronto, and is one win away from the competition final, where the winner will receive 1,000 ranking points.
  • It was the first time Williams and Osaka had played since the 21-year-old beat the veteran American at the 2018 US Open final, a match which saw Williams suffer an on-court meltdown.
  • But in the months since, Williams had been studying Osaka, saying she had been watching her “a lot” in her post-match comments.
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Serena Williams said she beat Naomi Osaka on Friday because she had been watching her “a lot” since her US Open meltdown, last year.

Williams beat Osaka 6-3, 6-4 to advance to the Rogers Cup semifinal in Toronto as windy conditions failed to put the veteran American off her serve, playing aggressively, and with an efficient return game that bested the 21-year-old.

“I knew her game a little bit more, so that’s a little easier,” Williams said post-match, according to The Guardian. “I’m just overall a little bit better. I know her game. I watch her a lot. I know what I need to do to hopefully try to get a win today, and it helped a little bit.”

A win for Williams sees her bounce-back after losing in disastrous conditions at the Arthur Ashe Stadium in New York, when the 37-year-old received code violations for coaching, smashing her racket, and calling the umpire Carlos Ramos a “thief” at the 2018 US Open.

Osaka beat Williams in straight sets that year, won her first Grand Slam title, then lifted the 2019 Australian Open trophy.

But since then, Osaka split with with her coach Sascha Bajin and has been unable to refind the form that saw her storm her way to a world number one ranking, suffering early eliminations in multiple tournamentsincluding a first round exit at the 2019 Wimbledon Championships, before coming unstuck against Williams in straight sets 6-3, 6-4 this week, in Toronto.

Read more: Naomi Osaka's humiliating first-round loss at Wimbledon was the latest misstep in her sudden fall from world No. 1

"We haven't played since New York, which was a really good match for her," Williams said of Osaka on Tennis.com. "I just wanted to come out and try to win a set this time, because she's beaten me twice."

Victory in Canada sees Williams claim her first win against Osaka, who still leads their personal rivalry 2-1. But Osaka has said defeat has not left her mad.

"I'm not really mad at this," Osaka said, according to The Guardian. "I think I played pretty well. And she just played amazing, which that's what she does."

Williams plays Marie Bouzkova in the tournament semifinal on Saturday.

The winner will proceed to the final of the Rogers Cup - the Canadian Open, a Masters event worth 1,000 ranking points - and face the winner of the other semifinal, Sofia Kenin or Bianca Andreescu.