Serena Williams has been knocked out of the Auckland Classic with a shock loss to fellow American Madison Brengle.
The world number two and top seed lost to Brengle, who is ranked 72 in the world, 4-6 7-6 4-6 in a see-saw second-round contest.
The final blow came as a double fault on a match point.
At a post-match news conference, Williams said the swirling wind had been a major factor for her.
"I really think I played - I'm trying to think of a word that's not 'obscene', but that's pretty much how I played. Eighty-eight unforced errors is too much ... just way too many unforced errors.
"I can't expect to win hitting that many errors. I just couldn't get used to the wind. My opponent played in the exact same conditions, so obviously she was used to it and her game was more suited for it I guess."
Brengle, 26, was 1-4 down in the first set before staging a brilliant comeback against the 22-times grand slam singles champion, who had constant trouble with her ball toss.
Williams was a set and 4-3 down when she made a comeback of her own, breaking with a drop shot and unleashing a running defensive forehand to clinch the tie-breaker and force the decider.
It was the 35-year-old's first tournament since losing to Karolina Pliskova in the semi-finals of the US Open last September.
Her sister, another major drawcard at this week's tournament, also made an early exit, forced out with an arm injury earlier this afternoon.
Venus Williams, who was the second seed, beat 18-year-old New Zealander Jade Lewis in their first-round match before announcing the injury was too bad for her to continue.
- RNZ / Reuters