Defending champion Caroline Wozniacki has crashed out of the women's draw of the Rogers Cup.
The top-ranked Dane was shocked by Roberta Vinci 6-4, 7-5 in the second round on Wednesday afternoon.
Wozniacki, who has won a WTA-leading five titles this year, was up 5-1 in the second set and looking to rally from a set down. However, the No. 22-ranked Italian stormed back with three break points to complete the upset.
Wozniacki had a bye in the first round and never really got going against Vinci, sending her return long on match point. Wozniacki also hit returns long twice at the first set point to give Vinci a lead she would not relinquish.
"I would have liked to have won that one and especially after leading 5-1 in the second," Wozniacki said. "It's not fun to lose this, but there's nothing really I can do about it now, just practice, and try to do better."
Windy conditions wreaked havoc with Wozniacki's serve in the first set, as the ball repeatedly floated away when she tossed it above her. She would double fault seven times in the match.
"It was very difficult at first with the wind," Wozniacki said. "Especially when you threw it up. It was going everywhere, so definitely that didn't make it easy. It was blowing in different directions, but it's the same for both players."
It will be Vinci's first appearance in the third round of the Rogers Cup in her third visit to the tournament. She has wins this year in Barcelona, Budapest and Hertogenbosch.
Vinci ranked this upset as a definite career highlight.
"This is the best victory in my life," the 28-year-old said emphatically. "I was 5-1 down but I knew that I can win the set because it was a lot of wind, so some mistakes.
"I tried to stay focused and play aggressive. That's it, this is the key why I won the set."
Meanwhile, the Canadian contingent at the tournament is down to one after Aleksandra Wozniak lost to No. 10 seed Samantha Stosur 6-3, 6-4.
The Blainville, Que., native has never made it past the second round in eight tries at the Rogers Cup.
"Well, it's disappointing," Wozniak said. "You play at home and you want to do so well. But I thought it was a good match, and I had a really tough opponent today."
Wozniak clawed back to 5-3 in the first set with beautiful cross-court backhand and an ace, but gave up any chance to rally when she returned the Australian's serve long to lose the set.
Wozniak got some help winning the first game of the second set when the wind took hold of a high lob and carried it inches over Stosur's side of the net. The 23-year-old Quebecer could only smile and shrug as her many supporters cheered her on.
"Obviously the conditions were pretty tough today," Wozniak said. "When you step on the court, you've got to be ready to deal with whatever comes in front of you, your opponent or the sun or the wind, and yeah, they were pretty difficult, but I tried my best."
Stephanie Dubois of Laval, Que., was set to meet world No. 4 Victoria Azarenka of Belarus later Wednesday.
Meanwhile, eighth-seed Francesca Schiavone of Italy eased into the third round with a 6-1, 6-3 victory over Russia's Ekaterina Makarova.
Schiavone capitalized on five of her nine break point opportunities to win in just over an hour, as play was temporarily halted shortly after the match due to rain.
Makarova, who advanced on Monday by eliminating Vancouver's Rebecca Marino, also lost to Schiavone in the second round at last year's tournament.
Joining Schiavone in the third round is recent Wimbledon champion Petra Kvitova, who battled Spain's Anabel Medina Garrigues to a 7-6 (3), 6-3 win.
The No. 7 seed from the Czech Republic came back from down 6-5 in the first set, blazing two aces by Medina Garrigues to make it 40-15. After the No. 33-ranked Spaniard netted a ball to force a tiebreaker she looked up to the skies and screamed "No!"
Rain halted the match at 4-2 in the second set but Kvitova came back and finished the job to book a third-round meeting with either Germany's Andrea Petkovic or Hungary's Greta Arn.
Earlier the day, a match between the top two Chinese players in women's tennis never materialized. Shuai Peng pulled out of her second-round match against world No. 6 Li Na with a left hip injury.
Peng, who came into the match ranked No. 16, said she first sustained the injury last week in San Diego.
"It is sad for her," said Li. "Always tough when you're playing same-country player. We train together, we know much (about each other). Always tough. I like to say sorry again for her."
Li will take on Stosur in the next round.
In Wednesday's other morning match, Lucie Safarova of the Czech Republic ousted Romania's Simona Halep 6-2, 6-4.