Torben Ulrich, his shoulder-length hair wringing wet and hanging in strands, sipped from a glass of grapefruit juice and explained why at age 50 he still enjoys travelling around the world for nine months a year to play tennis with a group of his contemporaries.

"It really isn't the money for me," said the man known in tennis circles as the world's oldest hippie because of his long hair and equally long beard.

"I still enjoy playing the game but more than that I enjoy watching myself and the others around me do battle with their decaying bodies. I enjoy watching how different people in our group handle the aging process."

The way Ulrich and about a dozen other older tennis stars have been handling aing since 1974 is to play the Grand Masters Tennis Circuit, an invention of Al Bunis, himself a top player in the 1950s.

This weekend, as a prelude to the Washington Star International, which begins first round play today at the Rock Creek Tennis Courts, Ulrich, former Wimbledon doubles champion Rex Hartwig and former Wimbledon singles champions Frank Sedgman and Neale Fraser showed their skills to Washington tennis fans.

Last night, Ulrich survived losing a second set tie breaker to defeat Fraser, 6-3, 6-7, 6-1, for the Grand Masters championship of the Washington Star International Tournament.

Although none of the four would claim to have the power of top-seed Guillermo Vilas of the speed of Eddie Dibbs or Harold Solomon, all are still in good shape.

"The point when this started was not to just get old tennis players who used to be great but to get players who were still in shape or played themselves back into shape," Ulrich said. "We can still play pretty well."

Ulrich, originally from Denmark, is a prime example of that fact. He is a physical fitness fanatic, running 10 miles a day when he is healthy and, in the opinion of some, he is playing near his peak.

But Ulrich, who tends to give enigmatic answers to most questions - "Do I run a lot? That depends what you mean by a lot" - isn't so sure.

"It's interesting to me to see how this old body is holding up," he said. "I'll say one thing, I'm glad we don't have to play six or seven rounds in each tournament. I don't miss that at all."

The Grand Masters usually play two or three days in each city, then move on, leaving them with four days to rest between stops.

"It's more sensible that way, don't you think?" Ulrich said. "That way we can get acclimated to a place before we play and be rested.

"Sometimes I think we paly much closer to our peak than the younger guys do because we don't have to play so much. It's almost impossible to play as much as they do today and not get tired and irritable.

"It's like with a group of musicians. When they travel constantly they never play their best. But when they're rested and have a chance to practice, they are at their best.

"You need to settle into a place, sniff at the atmosphere, get close to the earth before you can really appreciate the surroundings and perform in them."

Ulrich says the nonfinancial aspects of the Grand Masters tour appeal to him.Others, like Rex Hartwig, say the money is definitely a motivating factor.

All the players are under contract to Bunis and play for prize money in most tournaments although not in Washington. They all received a set fee and expenses for the Washington stop. Frank Sedgman earned $59,000 to lead the Masters money list last year. Tour prize money totals $300,000 this year.

"I've got a farm back home in Australia and six kids," said Hartwig, 52. "If it weren't for the money I definitely would not be spending nine months a year traveling."

For Hartwig, the Grand Masters tour arrived at a most opportune time. "If you think the situation for farmers here was bad, you should have seen Australia a few years back," Hartwig said. "The bottom fell out completely. So having an income off of tennis (Hartwig earned $28,000 last year) is a real bonus.

"What's more it's nice to still know I can play the game, I've never enjoyed it more. I know I don't move like I used to or hit as hard as I used to but I feel like I do. And it feels good out there."

None of the four men enjoyed Washington's humidity but the weekend matches provided crisp, competitive tennis.

"The thing about this tennis," said Ulrich, "is that you have different elements from the younger guys. We may not be as intense as they are because we've all proven ourselves. But the precision of the play may be greater because each of us knows that we have to rely on control rather than power."

Many of the players think Ulrich will still be playing at 70 because of his conditioning and his devotion to the game. But Urlich, a Buddhist, who practices yoga, says that is not so. "I'm enjoying being a participant and an observer of all this rights now," he said. "But in a week maybe not," or a year. There's much else to do for me."

But for most of the Grand Masters, given a reprieve from retirement, the same cannot be said. "This is the best of both worlds," Hartwig said. "I can still play tennis and I can earn an income. It's delightful for all of us." CAPTION: Picture, Torben Ulrich digs a backhand shot out of the clay surface of the Rock Greek tennis courts in Grand Masters play. By James A.Parcell - The Washington Post