AUCKLAND, New Zealand - Former world No. 2 Svetlana Kuznetsova stumbled to a three-set loss to unseeded Kiki Bertens of the Netherlands in the first round of the ASB Tennis Classic on Monday.

The two-time Grand Slam winner won the first set in a tiebreaker but struggled in windy conditions before losing 7-6 (6), 6-2, 7-5 in 2-1/2 hours.

Swirling winds on centre court at the Auckland Tennis Center contributed to combined 100-plus unforced errors, but 21-year-old Bertens, whose ranking climbed 120 places in 2012 to 63, kept her composure to clinch one of her best wins.

Kuznetsova took an extended break after dropping the second set to receive treatment for a foot injury but couldn't stop Bertens' momentum.

Unseeded American Jamie Hampton ousted defending champion Zheng Jie of China 7-5, 6-1 in 79 minutes and Pauline Parmentier of France beat seventh-seeded Christina McHale 6-4, 6-1 in the day's other upsets.

McHale, whose ranking peaked at No. 24 in August before slipping to 33 at year end, also struggled to find form in the wind.

Russia's Elena Vesnina had a 7-5, 6-3 win over 18-year-old Canadian wildcard entry Eugenia Bouchard, the junior Wimbledon champion. There were nine service breaks in the first set — six in the first seven games — but Vesnina eventually settled to win in 95 minutes.

Former champion Yanina Wickmayer, seeded third, started her campaign with a 7-6 (3), 6-2 win over Magdalena Rybarikova.

Greta Arn, the 2011 champion, was beaten 6-4, 3-6, 6-2 by Thailand's Nudnida Luanganam in the final round of qualifying but gained a place in the main draw as a lucky loser.

Arn will face top-seeded Agnieszka Radwanska after the withdrawal through injury of France's Kristini Mladenovic.

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