"It's funny to think of myself as a top player," mused the current superwoman of the Virginia Slims tour, Martina Navratilova. "It's hard getting used to being a star among the stars. But I'm a big name now and there's much more pressure on me because people expect me to win all the time."

Navratilova has not let her public down. She has won six consecutive tournaments and 29 straight match victories, both Virginia Slims records. She already has earned $138,000 this year.

But there are doubters - those who expect Navratilora's winning ways to cease when NO. 1 ranked Chris Evert, who has not played the Slims Circuit this year, shows up in Boston for the tournament. Navratilova's service and aggressive net game have produced a dismal record against Evert's imperturbable baseline approach.

"I haven't been able to play consistently against her," Navratilova admitted. "But the last couple of months I've been very consistent. And I think the layoff will affect her. And she won't feel as much pressure because she'll know people expect her to be rusty."

In ther last year, Navratilova has learned that for successufl tennis one needs more than raw strength, aggressive behavior and a desperate will. Everything about her life seems softer these days. Everything about her game is more subtle.

"I think I've matured over the last year. I feel a lot calmer. People expect you to grow up quickly when you're in pro sports, but it's hard to be everything to everybody."

The greening of Navratilova began two years ago with her difficult decision to defect them from her active Czechoslovakia. With the weekly paycheck no longer government-controlled, the 21-year-old Navratilova went on buying sprees that were the talk of the Slim's circuit. Self indulgence - and maybe, homesickness - plumped her already chunky 5-foot-7-inch frame to 167 pounds. She played hard, mean tennis. But there were no major victories.

The turning point, she says, came in 1976 when she decided she was getting lazy living in Southern California. "Besides, nobody, nobody out there gave a toot about me."

She moved to Dallas where she had friends, bought a house and, ultimately, found the kind of security she been lacking. "Things had been going downhill for me and when I got that house all of a sudden everything in my life seemed to turn around. I guess it was getting my roots."

She misses her relatives who still live in Prague. "I can't go back there now," she said. Her eyes show her vulnerability. There are long telephone conversations, letters, and packages with presents. "Yes, I'm homesick."

A toy poodle names racquet is her "family" now. She has lost 20 pounds wihtout even trying. The tendinitis that hindered her all last year is controlled by a blue rubber band she wears on her left wrist. She is battling shin splints, but that's because she plays through the final every week.

Can it last? Will the return of Chris Evert knock the carefully constructed props from under Navratilova's new calm life?

"Winning all these tournaments makes me feel good," she said with quiet confidence. "It makes me more determined for the future. It will be more difficult for me with Chrissie back. She's been No. 1 for the last three years.

"But there are two approaches to take when you play a play name. One is that you choke because you're openly scared of the big reputation. The other is you tell yourself you've got nothing to lose and you pull all the stops."

"I've never been scared of big names," said Navratilova.