Redskins cornerback Gerard Williams laughs off suggestions that he joined the notorious ranks of the National Football League's "criminal element" with the George Atkinson style shot he delivered to the back of Cleveland receiver Reggie Rucker's helmet in Monday night's opening preseason game.

Williams has taken a great deal of "criminal element" kidding from teammates that past two days, but the rash blow that resulted in an unnecessary roughness penalty was a psychological blunder that could cost Williams his role as understudy and heir apparent to the injured Pat Fischer.

How often Williams makes such costly mistakes during the remainder of the exhibition season will likely determine whether coach George Allen starts Williams or trades for a proven cornerback in the event that 17-year veteran Fischer is not ready for the start of the regular season.

"Williams has got to continue improving every game," said defensive backfield coach Ralph Hawkins. "If he does we can play and win with him. He's on the fence of becoming a good player right now.

He can become an excellent football player. But if he stays on the fence or goes back, he'll always be the third or fouth cornerback."

Williams was thoroughly introduced to psychological warfare, NFL style, by veteran wide receiver Rucker Monday night. The 15-yard penalty that displeased the Redskins coaches came two plays after Williams was called - unjustly he thought - for pass interference on Rucker.

"I was just trying to protect myself because Rucker was shooting at my knees and told me he was going to get me. I wasn't trying to club him: I just had a shot at him," Williams said.

"I guess because I was young, he was trying to intimidate me, get me upset. I was upset over the interference call and Rucker was pouring it on more. But it won't happen again."

It had better not, suggests Hawkins.

"Gerard made a mistake on the intereference call and he let that upset him two plays later and consequently we got a 15-yard penalty," Hawkins said. "It's like the golfer who three puts and then blows up with a double bogey on the next hole, and before you know it, you're out of the tourney. Here, you're out of the league.

Overall, Hawkins was pleased with Williams' initial start this season. The circumstances were nearly identical to the 1976 training camp when veteran cornerback Mike Bass suddenly retired because of a neck injury and Williams, in his first Redskins season, was thrust into a starting position while Allen shopped around and finally traded for Joe Lavender.

"It's up to me (to become a starter): it's a matter of getting some game experience and becoming a better ball-player by the end of the preseason." Williams said. "If he (Fischer) doesn't come back, I feel I can hold the corner down. I really feel confident this year and feel I can do the job. I'm a lot more relaxed."

Ironically, if Williams makes it big in the NFL, the Dallas Cowboys, the Redskins' most-hated rival, will get credit for discovering him. Actually it was Shirley Jones, Williams' aunt from Fort Worth, who made the difference for the Langston (Okla.) University athlete.

"We had a scouting report on him, but we were not beating the door down to sign him," said Gil Brandt, the Cowboys' vice president for personnel development. "She kept calling and asking us to sign him. She finally brought him in. That's the ironic part, his aunt was instrumental in signing him."

"Both my parents are dead." Williams said today, "and she king of looked out for me."

That was 1974, the summer of the players' strike. Brandt recalled that he was pretty impressed with Williams. He stuck around until the final cut and Brandt made arrangements for him to join Birmingham in the World Football League.

Williams immediately became a starter and led the team in interceptions with seven. He has a World Bowl championship ring and memories of five paychecks he failed to receive from the bankrupt team. But as Williams would say, things seem to work out for him.

Bobby Mitchell, the Redskins director of pro scounting, was scouting the WFL for free-agent prospects. Soon Williams was at Redskins Park. And so, here he is now, on the verge of being an NFL starter.