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Arn, ranked 88th and unseeded, also won three years ago at Estoril in Portugal.
The 23rd-ranked Wickmayer was seeded second.
While Arn sympathized with Wickmayer in defeat, she was unable to understate the value of her victory.
"I'm 31, you're 21. You have too much time to win other tournaments," Arn told Wickmayer.
While other player were accompanied to Auckland by coaches and trainers, Arn traveled alone. Her coach Vittorio Magnelli, the husband of former tour player Sandrine Testud, declined to make the trip, saying New Zealand was too far away "unless I buy a Concorde."
"He said he's traveled too much in his life," Arn said.
Copyright 2011 by The Associated Press
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