Williams and Osaka have both impressed so far in Toronto and they will headline the night session in a rematch of the dramatic New York showdown.
Last September, Williams blasted umpire Carlos Ramos after being given a code violation for coaching.
The American then demanded an apology from Ramos and called him a "thief" after being deducted a point for another code violation following a racket smash.
Osaka went on to win the final, her first Grand Slam title, but was reduced to tears as the emotions of the match got the better of her.
Williams has since apologised for her behaviour but the match is sure to bring out memories of the incident on Arthur Ashe Stadium.
“So whenever I get the opportunity to play her, like, it's something that I feel is a once-in-a-lifetime opportunity.
“And it feels more like I'm showcasing my skills to her, like, Look what I can do. You know what I mean? So I go into the matches with that mentality.
“And just super grateful to get the chance to play her.”
Coverage of the match will begin at 12:00 am Saturday.
Source: Express