Facebook's pro-am 'Mario Tennis' tourney includes the Williams sisters
Naomi Osaka and Kei Nishikori are also taking part in the charity event.
Mariotennisaces
Nintendo's NES Classic outsold Xbox One and PS4 in June
'Mario Tennis Aces' was the month's biggest-selling game.
Nintendo's 'Mario Tennis Aces' combines charm with surprising depth
And that was just the demo.We have two newsletters, why not sign up for both?
Get your first taste of 'Mario Tennis Aces' on Switch this weekend
You can play the game this weekend for free.
'Mario Tennis Aces' hits the Nintendo Switch on June 22nd
You'll be able to target special swings like an FPS.
