Sixth seed Nicole Vaidisova survived a comeback by determined Russian Alla Kudryavtseva before scraping through in three sets on Monday to advance to the second round of the ASB Classic tennis tournament.
The Czech took two hours and 37 minutes to win 7-6 (7-3), 4-6, 7-5 against Kudryavtseva, who is ranked 28 places lower in the world rankings at 68.
The former world number seven seemed to have the match sewn up when she took a 4-0 lead in the final set.
She went on to save five break points to go 5-2 up before the Russian clawed her way back into the match. Kudryavtseva survived two match points against the serve at 5-3 before dropping her serve in the decisive game.
Vaidisova, at 19 already the winner of six WTA Tour singles titles, suffered an injury-marred 2008 when her ranking dropped to 41.
"It's hard when you know you've had two match points on your serve," Vaidisova said afterwards.
"But I tried to hang in there, especially mentally."
Earlier Frenchwoman Aravane Rezai beat two-time former champion Eleni Daniilidou 6-3, 3-6, 6-3 in the tournament's opening singles match.
Last year's beaten finalist, whose world ranking of 97 is 55 places higher than Daniilidou's, dropped the second set due to crucial unforced errors, but had the edge in the decider.
American Jill Craybas, 34, beat 38-year-old Kimiko Date Krumm 6-3, 6-4 in the battle of the veterans.
Former world number four Date Krumm was playing in her first professional tournament outside Japan since coming out of a 12-year retirement last May.
Fourth seed Aleksandra Wozniak of Canada beat Slovakia's Magdalena Rybarikova 6-3, 6-7 (4/7) 7-5, while fifth seed Israeli Shahar Peer overcame Czech Petra Cetkovska 7-6 (7/4) 6-2.
Third seed Anabel Medina Garrigues of Spain had an easier ride through to the second round in her 7-5, 6-0 win over Italian Mara Santangelo.