So, if Osaka and Kvitova are both in the final, is the #1 up for grabs too, in a winner takes all?
Yeah whoever wins the title gets the #1 ranking. 11 women came in to this AO with a shot at number one. Halep, Kerber and Wozniacki all lost way too early to keep enough points to hold anyone off. So whether it's Osaka, Pliskova, or Kvitova, whoever wins this title gets #1.
But if Pliskova beats Osaka tonight but loses in the final she won't pass Osaka in the rankings. Because Osaka, by making the semis, is already at 5810. Going from R16 to the semis gives her 540 points. Pliskova made the quarters last year though. So if she makes the final and loses, she adds 870 points which only gets her to 5620. If she loses tonight she only adds 350 points, which will not move her above anyone that wasn't already going to fall below her (Kerber, Wozniacki, Svitolina.)
Kvitova, having made the final officially is now already at 6290 because she lost in the first round here last year. She'll be #2 if she loses the final.
Halep falls to 3 if Osaka wins tonight and 4 if Pliskova wins tonight because Osaka's 5810 is already higher than Halep's 5582.
Sloane Stephens stays ahead of Pliskova if Osaka wins tonight and rises to #4. Stays at #5 if Pliskova wins. She can't pass Halep. But Svitolina adds nor loses any points. So Stephens adds to their gap.
Kerber actually will stay ahead of Svitolina by 25 points.
Wozniacki will fall to #9 I believe. Behind Bertens ahead of Sabalenka.
Serena should rise to 11 I believe.
But definitely whoever wins it takes the #1 ranking.