Like the little girl with the curl, Australian tennis star Evonne Goolagong has always been a bit of a puzzle—to perplexed opponents and fans, to her guardian and mentor, Vic Edwards, and even, at times, to herself. At her best she is instinctively brilliant, moving around the court like a great tawny cat, smashing winners with pure grace and power. "When she's hot," concedes Chris Evert, now the world's top woman player, "there's no one who can beat her." Too often, however, Evonne's quicksilver genius deserts her and she wanders through a match like a sleepwalker. "Sometimes," admits the 23-year-old Evonne with a sweet-natured shrug, "my problem is that I relax too much."

Which Goolagong will be on display at this week's Wimbledon championships in England? Not even Evonne can be sure. "With me it just depends on how I feel. If I am in the mood to play, I play well."

In that respect, at least, Evonne has changed hardly at all since two instructors for the Victor A. Edwards Tennis School spotted her as a talented 10-year-old during a coaching clinic in her hometown of Barellan. One of eight children of an impoverished aboriginal sheepshearer and his wife, she had been given a racket by the local tennis club president and had developed an uncanny feel for the game. ("She just flowed around the court," remembers one of the instructors.) Summoned by a phone call, famed Australian coach Edwards himself made the journey to Barellan, a dreary little wheat-country outpost some 400 miles from Sydney, to offer the shy little girl his advice. By the time Evonne was 13, Edwards realized she was a potential world champion and persuaded her parents to appoint him her guardian. Moving to Sydney to live with Edwards, his wife and five daughters, Evonne began a new life in training for stardom.

Edwards didn't have to wait long. At 17, in her first year of international competition, she won seven of 21 tournaments. The following year Evonne thrashed her childhood idol, Australia's Margaret Court, to become one of the youngest champions in Wimbledon history. Since then she has won nearly every major tournament at least once, while establishing herself as one of the top three or four women in her sport. Last year Evonne earned more than $100,000 in official prize money, and another $250,000 in endorsements.

Despite her success, however, she has never truly lived up to her promise. Part of the problem, everyone agrees, is Evonne's wavering concentration. "Eva has more natural talent than anyone else on the tour, and that may be her biggest problem," explains her old friend Mrs. Court. "Most of the other top players, like Chrissie, have had to work hard to play well, and they have developed the concentration to do it. Eva has never had to work at her game."

As a young girl, whenever a losing opponent broke down in tears, Evonne would invariably fling her arms around the loser, then cry buckets herself. Even now, says Edwards, who accompanies her wherever she plays, she still lacks a certain remorselessness. "The fact is I don't think Evonne is a real pro yet," he explains. "She plays the game because she loves it, whereas a pro tries to win all the time. I don't mean that Evonne doesn't try to win, but it doesn't worry her very much if she doesn't."

Curiously, even some of Evonne's professional rivals are upset by her casual attitude. "She's infuriating to play against," says England's high-strung Virginia Wade. "Always smiling whether she's winning or losing. You get the feeling she just doesn't give a damn, and it throws you off."

Evonne, now playing World Team Tennis for the Edwards-coached Pittsburgh Triangles, is engaged to Roger Cawley, a 25-year-old Englishman (and former tennis player) who is a broker on the London Metal Exchange. They expect to be married in January and will eventually live in Australia. But Evonne plans to keep playing for two or three more years and doesn't believe marriage will hamper her. "In our opinion," says Cawley, "Evonne doesn't play well unless she's very happy. That's why we're getting married. We expect to be very happy."

Evonne says that whenever she does give up the game, she will do so without regrets. "Tennis has given me the opportunity to do a lot of things," she says. "To travel, to meet a lot of people, to buy my mother a house. [Her father was killed last year when struck by a car.] Even if I stopped playing tomorrow, I'd feel I achieved something. I'm satisfied. Winning is just not everything."