It has been 11 years since Ron Saul began a pro training camp as a second-stringer. But today, when the Redskins held their first full-squad workout at training camp, Saul found himself on the sidelines, watching Fred Dean playing in his place at left guard.

Saul knew the change was coming. He had heard scuttlebutt weeks before camp began, and he read about the switch in the newspapers. Still, until he showed up this morning and relized he no longer was a starter, he probable hoped things would turn out differently.

But now, at age 33, following four knee operations, Saul finds himself in the difficult position of having to reclaim a spot that has been his for the last five years, ever since he was obtained by George Allen from Houston.

He has had to scrap for playing time in the past. It seems every training camp for the last few sessions his job was being threatened by another player, only to have Saul wind up as the starter on opening day.

This time, however, it is different. He has lost his position before camp even began. It is not a matter of holding off a younger competitor, anymore. Now he has to show enough to convince the coaches to dislodge Dean, who is quicker and seven years younger.

"If anything goes wrong, let's just say the old pro is around and he'll be ready," said Saul, with a small grin.

"There's a youth movement on this team. They are going with younger players, I knew that. But I have to think I have a shot or I wouldn't be here. I haven't given up hope. The best I can do is go out, play hard and then let them decide what to do."

This was the first day that Coach Joe Gibbs could get a long look at his much-publicized, revamped offensive line. There were no surprises when the unit took the field. George Starke, a long-time starter, and Jerry Scanlan, the second-year man who has replaced retired Terry Hermeling, were the tackles; Dean and Melvin Jones, who spent last year on the injured reserve list, where the guards, and Dan Peiffer, who gained a first-string spot at the end of last season, was the center.

However, Peiffer didn't last long. He was kicked hard in the lower leg early in the practice and couldn't continue. At first the Redskins thought he might have a fractured leg but X-rays were negative. He will miss time, according to Gibbs, while the bad bruise heals.

Another veteran, Starke, was involved in an interesting experiment today. For awhile, he was moved to left tackle, where Hermeling once played. If Mark May, the No. 1 choice, develops fast enough at right tackle, then there always is the possibility Starke might compete against Scanlan on the left side.

A year ago, camp began with the starting line made up of Starke and Hermeling, Saul and Jeff Williams (since traded to San Diego) and center Bob Kuziel. Scanian was a free-agent rookie from Hawaii who was being converted from tight end to tackle. Jones was a seventh-round pick from Houston who had severe problems with pass blocking. Peiffer, once a starter at Chicago, was returning to the NFL after a two-year layoff from knee surgery. And Dean was a backup guard who wound up moving to tackle, where he beat out Hermeling until hurting a knee against Dallas and being sidelined the rest of the season.

When Williams was dealt in the off-season to San Diego for Wilbur Young, it opened up a position for Jones, the 6-foot-2, 272-pound strong man who has improved considerably in a year's time. And Gibbs and his staff chose in the off-season to promote both Dean and Scanlan, deciding it was time for the team to have an infusion of younger talent.

Hermeling,f who had started for 10 years, knew he, like Saul, would begin camp as a second-stringer. So he retired instead to Hawaii. But Saul decided he wanted to continue to play despite having a promising future with a private corporation that deals in waste disposal.

"I feel I can play one more year, at least," Saul said. "I really enjoy the game, but I realize that you can't last forever. It seems this is the only frofession where you start at age 10 and don't get paid until 12 years later. And then you're lucky to be around much longer.

"I've lasted 12 years when the life expectancy is four. This is my eighth head coach on just two teams, so there isn't much that can surprise me or be different.

"A lot of things can happen, injuries, people leaving camp. I'm in good shape, I feel good, and I want to play. So I'll just have to go out and keep going and see what happens."

It would be premature to count out Saul. He's a fighter, a full-sized bulldog who has clawed and acratched his way through a successful career despite less physical gifts than many of his peers.

Injuries have deprived him of some of his quickness, but not of his experience. He is clever and tough, and not about to concede to Dean, despite his rival's more impressive speed and agility.

"Fred's come a long way," said Saul. "He's put in five years and he's really improved into a fine football player. I realize what I am up against, but I've been here before. Seems every training camp, somebody is going to beat me out, so this is nothing new."

Dean also is aware of Saul's determination. It is not easy holding off a man who has the kind of pain threshold that allows him to have three teeth filled without the benefit of a pain killer. Saul is a throwback to the old-time, two-way player who ignored injuries and had his uniform soiled as soon as he left the locker room.

"They are really two contrasting styles," said Joe Bugel, the line coach. "Fred is smooth and flowing, he floats over people. Ronnie digs and fights and goes after you. He'll never let up. He's the kind of guy you like to have on your football team."

But Dean has been searching for a permanent position the last two seasons. He is gifted and young and the Redskins are trying to look to the future. And Saul realizes he has one foot in the past.

"It's a little different looking around the locker room and seeing all these new faces and not seeing the old ones," he said. "It's just something you adjust to. But we all should realize this isn't a 20-year job, even though I'd love to make it last that long."