It was a routine sweep during a routine 11-on-11 drill today, but there was nothing routine about the way Chris Hanburger reacted. He struck out his arm and clotheslined a rookie running back, who fell like a sack of potatoes.

It was supposed to be a no-contact drill, and Hanburger's teammates let out one of those collective special occasions and thumping hits, George Allen smiled, too.

Allen can afford to smile now, because he knows Hanburger will be with him for at least one more year, anchoring the defense from the weakside linebacking position and, most important, calling out the signals for the fourth straight year.

When the 1976 season had ended, Hanburger admitted today. "Yes, there was genuine doubt in my mind about coming back for another year."

There was the pain. A year ago, Hanburger suffered a knee injury in the final Dallas game, and then aggravated it the following week in the playoff loss to Minnesota. He decided not to play in the Pro Bowl because of it, although he said he had it drained the week before the all-star game and probably could have participated.

But there is still nothing they can really do to improve the aching back that has also plagued Hanburge the last few years.

"There's a lot of degeneration in the lower back," Hanburger said. "It's just one of those things. A lot of people have it. You can reinjure it by bending over, sleeping the wrong way, even swinging a tennis racket. It's just something you learn to live with."

Nevertheless, there are better ways to protect a hurting back than tackling running backs and blitzing quarterbacks. And Hanburger, the new Ford dealer in College Park, certainly has an easier way to make a living.

His thriving new business was another reason he says he very nearly decided not to play football.

"But there were a number of things that made me decide to come back," Hanburger said.

"For one, I enjoy football. If I can play another year and I can make a contribution, that's fine. The people working for me are excellent. I rely on them heavily and I depend on them heavily, and without them I really couldn't be here. I'm in touch with them every day, and they do a great job.

"But it's funny, I could still walk out of here (training camp) today and it wouldn't bother me one bit. A lot of people laugh at that, but mentally I've prepared myself to the point where if I play, I play, if I don't, I don't. It's no

"After last season, I was getting back into the business, and I was concerned about how it was going to go. But I never said anything about not playing to George Allen. He had no reason to suspect that I wouldn't play, because I never said anything to him."

Hanburger grudingly admitted that this most likely will be his final season of football. "But it's still a little premature, and I really shouldn't say one way or another. Basically, I'd say I'll probably call it quits, but you never really know."

He is on the option year of his contract a subject he also declined to discuss. There had been a report that he would not come to camp until he signed a new contract, but Hanburger denied ever making that threat. In fact, he was the first older veteran in town.

"The contract is my business," he said, "and nobody else's business. I've never felt the public has to know if a man signs or doesn't sign or what his problems are. It's a personal thing."

Turning to football, Hanburger was equally forthright when discussing the performance of the Redskin defense last season.

"We played well together last year considdring all the new faces we had, but we didn't play well enough," he said."

Hanburger also said he has never thought about the great contrast in his life. In his off-the-field career, he controls a million-dollar franchise, employs some sixty people and makes all critical decisions.

As a football player, he is one in 43, a man totally subservient to a coach who tells him when when to eat when to sleep and when to wake up.

"I guess it's just because that's the way I've always been brought up," Hanburger said. "If you're in a position of suppression, if that's the right word for this situation, then you do what you're told to do.

"You may bitch and you may not agree, but you do it or you get out."

Still, there are days when Hanburger does try and get away from all the pressures of business and football, particularly during the regular season. Often, he will simply head to the sky in a plane he owns with team dentist George Totten.

"I fly that plane any time I can," he said. "I'll do it on Mondays and occasionally even a Saturday before a home game. I'll just fly to Richmond or Frederickburg, stop and have lunch, then come on home.

"Whey, you fly, you can't take any of your problems up in the air because it requires total concentration. It's very peaceful and very rewarding, and I need that."