AFP - Former world No. 1 Caroline Wozniacki produced a spirited fightback to beat fourth seed Agnieszka Radwanska 4-6, 7-5, 6-4 and reach the Pan Pacific Open final on Saturday.
Awaiting the Dane in Sunday's Tokyo final will be Japanese teenager Naomi Osaka, who continued her fairytale run with a 1-6, 6-3, 6-2 victory over Ukraine's Elina Svitolina.
Wozniacki, Pan Pacific champion six years ago, starts favourite as she goes in search of a 24th career title.
But she had to claw her way back from 1-3 down in the second and third sets, finally ending Radwanska's resistance on her fourth match point by forcing her into a loose forehand, which she dumped tamely into the net after almost three hours on court.
Wozniacki's gritty display will give her confidence a further lift after battling back from a wretched run of injuries this year to reach the US Open semi-finals earlier this month.
Wozniacki's world ranking plunged to 74th after suffering wrist and ankle trouble, with her father even telling a Danish tabloid the 26-year-old could retire from tennis.
But despite losing the first set on a double fault, Wozniacki showed glimpses of her old form in an error-strewn match featuring 13 breaks of serve.
A whipped crosscourt forehand to take the initiative at 4-3 in the decider left Radwanska shaking her head and a full-blooded backhand drive to consolidate the break in the next game demonstrated why she used to be such a force.
Wozniacki, who carried her nation's flag at this summer's Rio Olympics, is looking to maintain her streak of having won at least one title in every year since 2008.