Fourth-ranked Agnieszka Radwanska beat American Jamie Hampton 7-6 (4), 7-6 (3) on Friday to advance to the ASB Tennis Classic final.
The top-seeded Polish star had dropped only 10 games on her way to the semifinals, sweeping her first three matches in straight sets, but was fully taxed by the 71st-ranked Hampton.
"Actually, it was very tough and I was just happy to be two points better in each set," Radwanska set.
Radwanska will face third-seeded former champion Yanina Wickmayer in the final. Wickmayer reached her third singles final in Auckland, beating eighth-seeded German Mona Barthel 6-4, 1-6, 7-6 (3).
"It was really tough today. It was up and down the whole match," Wickmayer said. "I started well, but she came out really aggressive in the second set, particularly against my serve. I went to the bathroom and thought it all through and focused on playing my best tennis. I was lucky it went my way in the third set."