Australian Fred Stolle missed out on the big money when he was one of the top tennis players in the world in the 1960s.

But players of his era, such as countrymen Rod Laver, Roy Emerson and Ken Rosewall, set the foundation for the modern professional tennis tour. And the solid footing they left for professional tennis by the mid-70s is rewarding a host of others. Professional tennis has become more popular than Stolle ever dreamed.

Stolle said that he never thought about the possibility that he would be playing at age 44 on a professional tour and that his opponents would include old friends Laver, Emerson and Rosewall.

But playing professionally once again is exactly what the 1966 U.S. Open singles champion is doing.

The four Australians are reunited and are touring on a grand prix circuit for players 35 and older, with a total of $400,000 in prize money spread over a dozen tournaments. All four will compete in Washington March 8 and 9 in a Master's Tennis Challenge--an exhibition, not a tournament--at George Washington University.

Stolle stays in shape by coaching Vitas Gerulaitis and Andrea Leand. "There are very few people who can live an active life in sports and enjoy it as long as a tennis player can," he said.

The program at Smith Center will match Stolle against two-time Grand Slam winner Laver. Emerson, who won more national championships than anyone else in tennis history, will meet two-time U.S. Open champion Ken Rosewall. In doubles, Stolle and Emerson will play Rosewall and Laver.

Stolle said the depth in tennis has improved greatly in the last 15 years but that the best players are on a par with the stars of the 1960s. "I don't think the top players are any better than Laver or Rosewall or other top players who played in those days," he said.

What has changed is the attitude toward competition, said Stolle, who runs a tennis club in North Miami Beach. That's because of money at stake.

"For the younger guys striving to get into the top 50, it is very competitive. If they don't win, they don't eat. The top 50 make a living but down from there they basically eke out a living."