NEW YORK (Reuters) - Caroline Wozniacki advanced to the U.S. Open final in dramatic yet heart-breaking fashion on Friday when China's Peng Shuai was forced to retire due to heat illness, putting the Dane one win away from winning an elusive grand slam title.
On another hot and humid day at Flushing Meadows, a packed Arthur Ashe Stadium had been enjoying a riveting baseline battle between Peng, one of the tournament's top servers, going against Wozniacki, one of the game's top returners.
But in an instant the mood turned from excitement to worry as Peng, without warning was overcome by the heat collapsing onto the court in agony and taken off away in a wheelchair, the contest ending in confusion, controversy and concern.
"It was really hard to watch for me whenever I saw her collapse on the court," said Wozniacki. "You know, tennis is great, but the health is more important.
"To see her struggling out there, I just wanted to make sure she was okay.
"I got the word that she's okay now and just getting cooled down, so that's great to hear."
Wozniacki was leading 7-6(1) 4-3 and closing in on victory when Peng suddenly grabbed at her thighs and stumbled to the back wall of the stadium court with what appeared to be severe cramping.
In obvious distress, the 28-year-old doubles specialist was eventually helped off the court and disappeared into the stadium where she was allowed to receive treatment.
A valiant Peng, playing in her first career grand slam singles semi-final, refused to throw in the towel, returning 11 minutes later determined to continue.
But after six points Peng was left curled up in pain on the baseline before the match was finally called.
A tearful Peng, who was consoled by her opponent, was then lifted into a wheelchair and taken from the court to a standing ovation.
Tournament director David Brewer was later pressured to explain why Peng was allowed to return to court with doctors having diagnosed her with heat illness and why she was not penalized for receiving treatment.
"She's a highly trained professional athlete," said Brewer, adding that Peng had received treatment at the site's medical center and had been cleared to return to her hotel. "She knows her body and her condition better than anybody. If she wants to go compete, that's why she's here.
"If there were a situation where she could have harmed herself, I'm very confident that our medical staff would have said, "Sorry, you cannot go back out there again"."
Under International Tennis Federation rules player are not allowed to receive treatment during a game or call for a medical timeout for cramping but can receive attention for more serious issues such as heat illness.
"The ruling was that she did have heat illness," said Brewer. "When they evaluated and they treated her, they treated her for heat illness.
"She never received treatment for cramping."
The events overshadowed what was superb performance from the 10th seeded Dane.
With 22 career titles and a stint as world number one, the single glaring hole in Wozniacki's resume has been a grand slam crown and she will now have an opportunity to correct that when she will take world number one Serena Williams in Sunday's final.
"It would mean so much to me. I have been close before," said Wozniacki, who lost the 2009 final in straight sets to Belgian Kim Clijsters. "I would love to win it and have a grand slam under my belt.
"It would definitely have the media stop talking about my lack of a grand slam, so that would be nice."
Peng, who had not dropped a set on her way to the semi-finals, had looked capable of taking one more step to the final as she got the match off to a determined start.
Twice Peng took the initiative in the opening set with a break but a relentless Wozniacki broke right back on both occasions, the second time at 6-5, to force a tiebreak.
Wozniacki dominated the tiebreak, winning 7-1, to take the first set of the tournament from her unseeded rival.
Peng quickly regrouped and broke Wozniacki at the first opportunity in the second but again the Dane had an immediate response breaking right back as her opponents game began to unravel.
"Mentally it's hard. It is 30 degrees Celsius out there; heat rule is in. It's hot and humid," said Wozniacki. "You lose the first set and I think that's pretty devastating in your head.
"For me to get that first set under my belt was really great. I felt good, and I was like, Okay, this is my match to take now."
Editing by Frank Pingue/Gene Cherry