Petra Kvitova battled past a resurgent Venus Williams to set up a showdown with Angelique Kerber in the Toray Pan Pacific Open final.
The world No 11 saved 11 break points on her way to a 3-6 6-3 7-6 (2) victory in two hours and 24 minutes to reach her third tour final of the season.
The 33-year-old Williams served nine aces and broke seventh seed Kvitova twice but she fell short in the deciding set tiebreaker after her opponent raced into a 6-0 lead.
"Every game was up and down, and it was about a few points," said 23-year-old Kvitova. "I always love playing here. I had a great result in 2011, when I reached the semi-finals and I love being on centre court before a great crowd."
Kvitova will face Kerber in the Tokyo final after the world No 9 overcame fourth-seeded Caroline Wozniacki from Denmark in straight sets, 6-4 7-6 (7/5).
The German took advantage of three of her nine break point opportunities to seal victory in one hour 40 minutes.