After 10 days of interesting personalities and unexpected twist, the women's singles of the U.S. Open tennis championships ended today the way everyone had expected it would. Chris Evert won.

But, unlike last year when she lost only 12 games in six matches, Evert had to struggle. Wendy Turnbull pushed her more than any player has here since Evonne Goolagong in the 1975 final.

Evert was down service breaks at 3-4 and 4-5 in the first set before beating the surprising 24-year-old Australian, 7-6,6-2, in a one hour, 28 minute match that delighted 12,587 sweaty-palmed spectators at the West Side Tennis Club.

Evert, 22, is the first player to win three successive titles here since Maureen Connolly - a player with whom she is often compared for her back-court consistency, in 1951-52-53.

Evert has now won 113 consecutive matches on clay courts, spanning 23 tournaments, since Goolagong beat her in the final of the Western Championships at Cincinnati on Aug. 12, 1973.

Evert said she was thrilled by that astonishing streak a record for the modern era in tennis. "I'm very proud of that static," she said. "I've won all the major titles except the Australian (which she only played once, losing the 1974 final to Goolagong), and I'm at the stage where I need new goals to keep me motivated."

Evert has won two Wimblendon, two French, two Italian, four Virginia Slims, and now three U.S. Open titles, plus close to $1.5 million in prize money ($3,000), since bursting upon the scene here at sweet 16 in 1971, reaching the semifinals exactly 20 years after Connolly had won the title at the age.

Today, after increasing her astounding five-year pro record to 513-45, Evert remembered her first U.S. Open nostalgically. She knows this may well have been her last appearance at Forest Hills, since the tournament is moving to a new facility Flusing Meadow, possibly next year.

"I haven't thought about that up until now, because I wanted to concentrate on the tournament," she said. "I feel sad in a way because I have a lot of good memories about playing at the West Side Tennis Club. As long as I live, I'll never forget that first year, when I was 16."

Turnbull will never forget this year, when she beat Rosemary Casals, 4-6, 6-0, 6-0; Virginia Wade, 6-2,6-1; and Martina Navratilova, 2-6, 7-5, 6-4, to emerge from the shadows of anonymity about her own abilities.

"I'm not really disappointed. I never expected to be in the final, and I was happy with the way I played," said the pert and suddenly self-assured former bank teller from Sandgate, New South Wales, who collected $16,500 and an incalculated quantity of respect.

She gave it all she had, worrying Evert with the speed around the court that has earned her the nickname "Rabbit," retrieving a number of apparent winners, mixing her game up cleverly.

Sometimes she served and volleyed, other times she stayed back and looped forehands high to Evert's backhand, waiting out opportunities to scoot in for volleys.

She did not win a point the first three times Evert served, started with a double fault, labored to hold her serve after four deuces and three break points in the fourth game, but then surged ahead in the first set as the underdog-loving crowd urged her on.

She broke in the seventh game after finally grasping her first point against serve by drawing Evert in with a drop shot and passing her with a forehand down the line.

The Evert double-faulted, and from 30-30 knocked a forehand wide off a 32 stroke rally and a backhand wide after 16 strokes.

Turnbull promptly lost her serve at 30, making four errors, but broke again at 15 for a 5-4 lead. Turnbull played two attacking points to get to 0-40, and Evert hit a backhand long for the break.

But serving for the set, Turnbull again played a terrible game. She netted a backhand, double-faulted (her third of four), and sailed two forehands long.

Into the tiebreaker they went at 6-6, and Evert icily asserted her celebrated match toughness. Turnbull sliced a backhand long for 0-2 and never recovered.

The key point came when Turnbull served at 1-4; she got to the net behind a good, deep forehand approach, and Evert passed her with a buzzing backhand own the line.

Evert double-faulted at 5-2 but closed out the best-of-12 tie-breaker, 7-3. The first set was over, it had taken 54 minutes. The second went much quicker, after Turnbull double-faulted to lose her serve at love in the first game.

Turnbull had one chance to get back in the match, at 30-40 on Evert's serve in the sixth game. She hit a backhand that was called long - the crowd howled in protest, but lineswoman Pat Brummer would not change her call - and Evert reeled off the next six points to hold and break at love, building an unassailable lead. She served out the match from 15-40. Turnbull floating a backhand long on the first match point.

"I though I stood a good chance of winning when I served for the first set," said Turnbull, "but Chris plays awfully well when she's behind . . . She is so tough in tie breakers. And when I let her break me to start the second set, she just went away with it."

And so in the end, after 43-year-old transsexual Renee Richards, 14-year-old prodigy Tracy Austin and emerging star Turnbull had flitted across the stage, enjoying their moments in the spotlight, the leading lady of tennis was fittingly left for the final curtain call.

"I hadn't been pushed the whole tournament, but I wasn't going to let anything get me down today - the crowd, Wendy's ggod play, or anything else," said Christine Marie Evert, a trouper and a champion.