When Warren Wilkerson, 29, a car salesman and sometime semipro quarterback, heard that the age cutoff at Saturday's open tryout for the Washington Federals was 28, he decided to lose a year.

"I'm 28 again. Happy birthday," he said. Then he went into his rap.

"I can taste it," Wilkerson said, starting to dress for the workout. "I'm fulfilling a destiny. I've been a quarterback all my life, on and off the field. A leader of men."

Wilkerson handed his chocolate-brown leather jacket to one of the friends who had driven him from White Plains, N.Y., to RFK Stadium. "My friends are here for an entourage security-type effect," said Wilkerson, donning a Steelers jersey.

He described his meticulous preparations for the tryout, right down to the last lap and poached egg, then fell quiet. He smoothed out his sweats, tied his bandanna and shot quick, confident glances at the 617 other men who had come to RFK Stadium on a cold, clear morning in hopes of signing that very afternoon a professional contract with the United States Football League team.

"It's America's dream," said Wilkerson.

Most of the young men there running 40-yard dashes, 15-yard back pedals and five-yard out patterns were dreaming of a chance at the limelight, a chance to sample the cash and competition that professional football can provide.

There were electricians, construction workers, teachers and students, all giving it a try. There were men who looked as though they might have trouble climbing three flights of stairs, men who came on a dare or a bet and men who had at least one of the qualities -- speed, agility, strength and experience -- that says potential.

There was Alan (White Lightning) Thompson, who works for Walter's Floor Service in Hyattsville. He ran sprints in front of the coaches as his girlfriend Diane Yslas, a cheerleader for the Bullets, watched nervously from an end zone seat.

There was Dave Morrison of Temple Hills, an assistant pathologist who does autopsies. "It's good work if you've got the stomach for it," he said. As much as he likes his job, though, Morrison was looking for work in a different line: the offensive line.

And there were two old pros.

Manny Sistrunk, after six years with the Redskins and five with the Eagles, retired two years ago. He now lives in Forestville, where he works with retarded and emotionally disturbed children. He's 35, but at 6 feet 5 and 265 pounds, he felt he could help a club with his size and experience.

"You don't play as long as I did and not miss it. I'm in real good shape," said Sistrunk. But his time in the 40-yard dash was 5.3.

John (J.J.) Jones played behind Joe Namath for the New York Jets in 1974 and 1975, then played in the Canadian Football League until 1978. Since, he's played semipro ball with the Binghamton Jets and the Syracuse Americans.

"I haven't lost anything," said Jones, 30. "Haven't lost anything but time. Just time." But his passes fluttered and sailed. The calendar told the story.

General Manager Dick Myers said the Federals want to go to their Florida training camp this winter with 90 players. While the team has announced only 40 signings, he has signed about twice that many. Also, the USFL is holding a college draft Jan. 4, two months before the league begins its 18-game regular season.

"Between the roster we've already got and the draft, it's going to be very tough for many people here to make it," said Myers. But like most of the other teams in the league, the Federals were hoping an open audition could do for them what it did for the Redskins in 1972, when George Allen discovered kick return specialist Herb Mul-Key.

Coach Ray Jauch could not attend the session -- he is coaching the Winnipeg Blue Bombers as they go after the CFL's Grey Cup -- but Mike Faulkiner, director of player personnel, was there, along with temporary assistants such as Terry Metcalf and Frank Graham.

As morning became afternoon and the day wore on, dreams died quickly. A blown 40-yard dash, a dropped pass, a pulled hamstring and it was over.

The Federals signed three players -- defensive end Tim Swords, defensive back Paul McKinney and linebacker Mike Lemon.

The old pros, Jones and Sistrunk, were circumspect, and those who came on a lark at least left with a story for their children. But for some of the more talented younger men, men who perhaps once made a play that suggested, however vaguely, that a professional career was a possibility, the disappointment was stark.

Arnold Goodgame, a 240-pound policeman from Cleveland who had hoped his 4.6 time in the 40-yard dash would earn him a berth at fullback, seemed to be making important decisions on the basis of the unsuccessful tryout. "I've tried out for 13 NFL teams and I tried here," he said. "I've got to realize I can do other things in life."

Wilkerson, the car salesman, found he couldn't set back the clock after all. His passes will make him the star of the sandlots, and possibly a semipro league, for a few more years, but he knew he had come up short as a pro.

He said he and his entourage would travel to other open camps. "I've been training too long for this to be disappointed," he said. But his face, so alive and smiling before the tryout, said otherwise.

One member of the entourage took shots of Wilkerson as he ran, threw passes and talked with a reporter. He seemed to enjoy the attention, but Warren Wilkerson knew it wasn't real. It wasn't halftime highlights. It was only home movies.