LONDON -- American Alexandra Stevenson, older and wiser than the outspoken teenager of two years ago, turned up the heat in her Wimbledon comeback with a 2-6, 6-4, 6-4 first-round victory against Italian Tathiana Garbin on Tuesday.

Stevenson reached the semifinals after getting into the tournament as an 18-year-old qualifier, but she faced the indignity of having to qualify again this year after sliding down the world rankings from a career-high 33 to 111.

But Wimbledon organizers, mindful of her place in the tournament's history as the first woman qualifier to reach the last four, awarded her a wild card.

Her match with Garbin was more memorable for the use of a new "extreme heat rule" than for the quality of the tennis.

Australian umpire Leanne White called a 10-minute break at the start of the third set under a rule, being used at the championships for the first time, which allows players to request a respite if the temperature reaches 82.4 degrees Fahrenheit.

Garbin, a plucky and entertaining player who chased down every ball in the searing heat, had summoned the trainer one game earlier for a massage of her right thigh.

Stevenson, 20, said the break had taken her by surprise but she had tried not to let it affect her concentration.

"I just walked to the locker room and put cold water on my face and walked back," she said. "I just tried not to lose my focus."

A foot fault called against Stevenson as she was serving for the match provided further distraction on court 14.

"I just tried to not let it fluster me and keep going," said Stevenson, who went out in the second round 12 months ago during a poor year dogged by injury.

The third set was watched by defending champion Venus Williams, who won her own first-round match earlier on Tuesday and sat with Stevenson's mother, Samantha.

"We are friends, we grew up together," Stevenson said. "She gives me nice support."

Samantha Stevenson, a journalist, has not endeared herself to her daughter's fellow players or to the media with her outspoken views.

She was reported to the Women's Tour Association at Edgbaston earlier this month for tearing down a display of press cuttings about her daughter's third-round exit and has made allegations of racism on the tour.

Her daughter, articulate and more thoughtful than of old, said she had learned much since bursting on to the Grand Slam scene with such force two years ago.

"I have learned that people interpret what you say differently and you have to be careful," she said.

"I have matured on the court, and I actually have a clue what I am doing now. Two years ago I was a wide-eyed young child straight out of high school."

Asked if she had any regrets, the player said she regarded the past two years as good experience.

"There are always trials and tribulations that you go through," she said. "You cannot go through life without some ups and downs."