Past tense is the dominant manner of speaking at the $40,000 Prudential-Bache Securities Grand Champions Tournament at Rock Creek Tennis Stadium.

Nobody understands that better than Jaime Fillol.

"We're not trying to show we're better than the other guy. That time is past," he said yesterday after eliminating Eddie Dibbs, 6-2, 6-4, before 800 spectators.

To play the Grand Champions circuit, one must be at least 34, plus the small matter of either having won a Grand Slam title, held the No. 1 ranking in a country or played Davis Cup.

No problem for Fillol, 39, who led Chile to the 1976 Davis Cup final.

"If I get beat, it's okay," he said. "Tennis doesn't take all our time anymore.

"Everybody has a family. We don't practice too much. If we were on the Grand Prix circuit day in and day out like we used to be, we'd still play quite well. Not as well, but we'd do all right."

For a professional athlete, aging is surely an even more difficult process to face than for everyone else. Tennis players make their living from the strength of their serve, the accuracy of their strokes. When the body begins to refuse requests it once carried out to near perfection, it is a difficult time for an athlete.

Fillol said, "When I was 31, 32, 33, 34, during that time people say, 'Well, why do you keep playing? You're not as good as you used to be.' (Guillermo) Vilas is going through that now.

"You ask yourself, 'Why should I stay on the circuit when I'm not winning?' I don't think that's the reason to quit. If everything is okay -- my life, my family -- there's not really any reason to do something else."

Fillol, who lives in Santiago, Chile, with his family, said tennis players maintain, and often even improve, technical skills as they age, but they lose strength and stamina.

"The younger guys can muscle it," he said. "For us, it's finesse. If I knew 10 years ago the technical things I have learned, I would have been a better player."

In other matches, Andrew Pattison eliminated Sherwood Stewart, 6-0, 6-1; Ray Moore, who strained his back yesterday morning, forfeited to Bob Lutz, and Colin Dibley beat Charlie Pasarell, 6-2, 6-0.

Play in the round-robin tournament will continue today at 5 p.m., with semifinal and final matches Saturday and Sunday.