SHE AND HER HUSBAND ARE IN THE SAME BOAT : Magers at Home on Water, Clay, Grass . . .

Pittsburgh is known as the city of Three Rivers, but growing up there did little to prepare Gretchen Magers for life at sea.

The fresh but not so clean waters of the Monongahela, Allegheny and Ohio rivers bear little resemblance to the salty Pacific Ocean. And life on the Gypsy Lady is far from the hills of Pittsburgh, even if the 34-foot sailboat spends most of its time docked at Harbor Island.

“All I had done with boats was canoeing,” Magers said of her nautical training while growing up in the Pittsburgh suburb of Mt. Lebanon.

But for another year at least, the Gypsy Lady is home for Magers and her husband, Stephen, a graduate student at San Diego State. That is, when Magers is not out on the professional tennis tour.

This week, she is combining a visit home and her work. Magers is competing in Great Bank American tennis tournament at the San Diego Tennis and Racquet Club.

In tonight’s final match on center court, Magers will play in the second round against Angelica Gavaldon, a 15-year-old junior from Our Lady of Peace High School. Gavaldon is coming off a three-set upset of eighth-seeded Ros Fairbank.

“You can’t go in worrying about her,” said Magers, 25, who beat Pascale Paradis, 6-1, 7-5 in her first-round match Monday. “I have lost to 15-year-olds before, and it is going to happen again. I can’t worry about her age.”

If Magers sounds undaunted by the prospect of facing an amateur with nothing to lose, it probably is because she is playing as consistently well as she has in some time.

She is coming off her best Wimbledon, where she reached the quarterfinals before she was eliminated by eventual runner-up Martina Navratilova, 6-1, 6-2. She also has a two-set victory over fifth-ranked Arantxa Sanchez, the French Open champion from Spain, in the Players Championship in March.

“I’ve had some of the best wins of my career this year,” Magers said.

The most exciting probably was her second-round Wimbledon match against ninth-ranked Pam Shriver. The match was long and tense, with Magers winning the final set of the three-set match, 12-10.

Magers went on to reach the quarterfinals of a Grand Slam event for the first time since she did it in the 1983 French Open as a 19-year-old freshman at Trinity (Tex.) College.

The next year at Trinity, she met her future husband.

Stephen was on the football team, but it was in biology class that the two became friends. They married in December 1986 and moved to San Diego the next year.

San Diego was an ideal location because Stephen could work on his master’s degree in exercise physiology while Magers took advantage of the climate and availability of other pros to work on her game.

“There are tons of tennis players our here,” Magers said, “and the weather is even better out here than Texas.”

When they first arrived, they took an apartment in La Mesa. But after a few months of paying rent double what they were used to San Antonio, they thought of getting a place of their own. Their problem was no different than that for any potential first-time home buyer in San Diego--sticker shock and economic uncertainty.

“It might be more psychological than the actual burden of it,” Magers said. “We were renting a small house in San Antonio for $350. We were in a condo out here, and it was $750.

“We were only going to be here for two years for sure, and we really didn’t want to get into a house. Stephen doesn’t have a job yet, and my job is up and down. I can get injured this afternoon. We just weren’t ready for the responsibility of a house.”

The boat, Magers quickly points out, was her husband’s idea.

“It was something that he kind of always wanted to do, which he never told me before,” Magers said. “I came back from a trip and he told me, ‘Let’s go down and look at some boats.’ I said, ‘Why?’ ”

Stephen had a sailing background from his days growing up in Houston and sailing in Galveston Bay. “As much as I enjoy tennis,” Magers said, “he enjoys sailing.”

And he was itching to get back on the water. He also told her a boat would be a good investment.

Magers was not so sure. But in the spirit of marital harmony, she went along. Almost two years later, she has even found it in herself to work up some enthusiasm for the adventure.

“It has been a great experience,” Magers said. “We have met some really fantastic people that, if we lived in the condos, we wouldn’t have been exposed to.

“We’ve gotten a lot more out of it than we thought we would--the pleasure we have had sailing and living a different life style. We were up there in Yuppyville up there in one of the condos, and it is real easy to go along with what everyone else is doing.”

Although some luxuries are missing (“We don’t have a Cuisinart,” Magers said) and her doubles partner this week, Robin White, has possession of her stereo and futon, it is not as though the Magers are roughing it. The boat has two berths and is equipped with most all of the modern conveniences, including a microwave and VCR.

And because Magers spends so much time on the road and outside when she’s in town, the small living quarters do not seem too confining. As for taking the boat out to sea, Magers usually leaves that to Stephen.

“I do a little bit when it is good conditions,” Magers said. “But I get a little nervous. I’m still not real confident. When the wind starts blowing really strong, I’m really not confident. I’m much more confident being the crew and doing what Steve tells me to do.”

Land is where Magers is at her best--no matter what the surface.

She has reached the quarterfinals of Grand Slam events on three different surfaces--1982 U.S. Open (hard court), the French (clay) and Wimbledon (grass).

She excels in no one facet but has no great weaknesses, either.

Magers has risen steadily through the rankings this year, starting at 41 and reaching 33 after her Wimbledon performance, her highest since she was 28th as an amateur in July 1983. She entered play this week ranked 36th and with yearly earnings of $107,441, having already exceeded her record $96,160 of last year.

By these measures, she is having her best year as a pro. But Magers strives for more. She wants a shot that will strike fear into her opponents, like Steffi Graf has with her powerful forehand.

“I’ve never really had a big shot other than when my serve is on and just being quick,” Magers said.

That is the edge she said she needs to make a big jump in the rankings and reach the level where she contend more consistently. In three years as a pro, Magers has two tournament titles--1987 in Auckland, New Zealand, and 1988 in Schenectady, N.Y. Her best finish this year was again in Schenectady last week--a 6-4, 6-3 semifinal loss to Laura Gildemeister.

Magers said that because months and sometimes years between tournament victories can be discouraging, it is important to get the most out of the near-victories.

That is why the success of the past few months has infused her with renewed dedication.

“I have been very fortunate to have good results spaced out,” Magers said. “Just when I’m about to get discouraged, I get a good win. It has taught me to hang in there. Something good might be around the corner, right when you are about to quit.”

Magers is hardly at the end of her career, but there is always time for reflection. Her immediate plans are clear--play tennis and live in San Diego for another year while Stephen finishes his work at SDSU. After that, much may depend on Stephen’s plans. SDSU does not offer a doctoral program in his field, so if he continues his studies, it might require a move back to the University of Texas in Austin.

Magers said the two have an understanding that while he is in school, her tennis will pay the bills. But Magers said she looks forward to the time when she can stay at home and let Stephen go off to work.

“We understand that this is the way it is for right now,” Magers said. “I’m really going to enjoy those days when he is working, and I am staying at home, going biking all the time, doing what I want to do. I am looking forward to those days.”

But will those days include the Gypsy Lady?

“Hopefully,” Magers said, smiling, “we will get a house and have a smaller boat, and it will be more of a hobby.”