If Anne Smith, who won the women's singles title at the U.S. Amateur Indoors on Sunday in Salisbruy, Md., had a battle cry, it would undoubtedly be "Praise the Lord and pass the Dr. Pepper."

The talented, aggressive 18-year-old from Dallas is one of the most confident young prospects on tennis.She believes in herself, in God, and in "the most original soft drink in the whole wide world," which has its headquarters in her hometown.

A devout Christian, "Annie" has been known to ho on court with Biblical passages taped to her racker handle for inspiration. And last ball, touring the People's Republic of China as part of a U.S. team (four juniors, foru pros), she took along one suitcase of clothes and another of Dr. Pepper.

"I knew I wouldn't be able to buy any over there." she explained matter-of-factly. Apparently the thought of drinking tea at change games didn't appeal to her.She allowed as how she would have taken a supply of Big Macs, too, If there had been any practical way to do so. After all, one doesn't know how the forehan volley will react to bean curd soup.

But if she lacks the spirit of adventure in food and beverage. Smith shows no discernible fear or hesitation on a tennis court. Her inclination is to attack boldly, she loves to play before crowds and her self-assurance is total.

Many of those who have watched her over the past year consider Smith a "can't miss" future star of the women's game, along with Tracy Austin, already No. 4 in the U.S. women's rankings at age 15, and Pam Shriver, 6-foot-1. 15-year-old high school sophomore from Lutherville, Md.: whom Smith beat in a three-set final at Salisbury.

Smith, a freshman at Trinity University in San Antonio, Tex., seems to have all the equipment needed to fulfill her aspirations to a pro tennis career - ambition, determination, poise, improving ground strokes, a splendid net game and apparent imperviousness to jet lag.

Consider her itinerary for six weeks last summer:

She flew from Dallas to Rome, where she reach the semifinals of the Italian International Juniors, her first tournament ever on slow European clay.

After jetting back across the Atlantic and spending one night at home, she flew to Los Angeles and won a prestigious junior tournament on fast cement, the surface she grew up on.

She returned to Dallas long enough to attend her hraduation from Texas Christian Academy, then flewthe next morning to Paris to play in the French Juniors, and became the first American girl to win it.

She left Paris at 6:30 the evening of her next morning, and was on a.m. the next morning, and was in court for her first match in the Texas Juniors eight hours later. The following Sunday, she won that tournament.

Back out to the airport after the final, she flew to London and caught of Eastbourne, 65 miles to the south. There she won three qualifying matches to earn a berth in the women's singles draw at Wimbledon.

Smith lost a tough three-setter in the second round at Wimbledon to her tennis idol, Billie Jean King, a result that was repeated in the U.S. Open in September.

"Gee," Billie Jean said after barely surviving a scintillating match on the stadium court at Forest Hills, "she sure reminds me of me at 18."

The resemblance was not lost on other observers. Smith is much thinner than BJK was as a chubay teen, but she has the same bouncy exuberance and zest for the net. Her vooley is outstanding, as are her anticipation and agility.

A 5.5, 117-pounder, Smith is quick and wonderfully athletic. Last year, as a high school senior, she scored 50 pionts in the first half of a basketball game.

"Our coachwouldn't let me play most of the second half because we were killing the other team, but I got in again for the final minute and finished with 54 points. I don't think I missed a shot," she recalled. A forward, she averaged more than 30 points a game.

Her father, Dallas orthodontist John Lee Smith, advised her at attened Trinity, where she is on a scholarship and has consideerable time off to play tournaments. She is majoring in communications, taking courses in French, Spanish and speech, but says, "Mainly, I study tennis."

Smith is not as demonstrative as King on the court, but has a crowd-pleasing flair. "I like putting on a good show," she says. "I think spectators like to see explosive shots - volleys and overheads - and I love to entertain them."