The American is enjoying his first Top-10 season and aims to finish the year on a positive note.
Ben Shelton blasted a 105 mph forehand winner that jolted the tiebreaker and quarterfinal in his favor.
The talented Shanghai native faces Sabalenka for a spot in the semis.
"I'm actually glad the crowd wants to get into it, because it means that the match is interesting," Novak Djokovic said.
"I saw I'm playing first match and was, like, wow, that's a little bit strange scheduling," Jelena Ostapenko said after bowing to Coco Gauff.
The Belarusian says she owes Swiatek gratitude, and looks forward to more battles with her.
"I think [Madison Keys is] a bigger hitter on tour than a Sabalenka or an Iga or even a Rybakina," said Jessica Pegula.
