Vika started the tournament in 32nd place in the WTA Race. If Ons advances and Vika defeats her tomorrow, she'll end the tournament at #10, likely in position to earn a spot at the WTA Finals (assuming Barty and Osaka are both out).
Ons looked tired last night. The commentator made similar remarks. I think Ons' stamina has improved recently, though. She has been playing a lot recently and didn't even go back home after US Open since she played Chicago.
Badosa seemed familiar and ready in handling many of Ons' patterns and dropshots (not surprising since they're friends).
The level of the WTA's top 100 is insanely high right now, everyone can get a big title. This is probably the most important legacy of Serena and Sharapova (a bit), in order to compete with them everybody has to be top level athlete.