For a franchise that has had three coaches in the last five years, these "new eras" are becoming as familiar to the Redskins as the sight of Joe Theismann pushing some product on television.

But coaching changes aside, there was something different about Joe Gibbs' opening training camp practice today. The players seemed so young. And so big.

And there was Gibbs, up amoung his giants, leading preworkout calisthenics, full of the enthusiasm that seems to characterize this new coaching staff.

This was the start of a special 10 days for Gibbs and his players. Before the bulk of the veterans report July 24, the coaches will have a chance to teach and coax and prod these potential proteges without worring about the pressure of roster cuts and preparations for exhibition games.

Thanks to a string of minicamps that took care of introductions, no one stood around and watched. The players were subjected to contact work that will separate the prospects from the early cuts.

"I thought we looked kind of rough," Gibbs said later. "You look a lot slower on grass and with pads on then you do on artifical turf. But it was good to get out and start working."

Rookies didn't make George Allen's teams. And as far as Bobby Beathard is concerned, not many pleased Jack Pardee, either. But Gibbs doesn't have similar reservations about inexperienced, fresh-off-the-campus athletes. He can't seem to collect enough of them.

These young giants are the Redskin future on display. The time to break with the past finally has come. The Over The Hill Gang and all the rest of the symbols of the past decade of pro football in Washington no longer apply to this team. A dozen or more rookies could wind up on the final roster.

Of the 58 players participating in the opening days of this camp, only three played for Allen. Only seven made Pardee's 43-man foster last year. But as many as 10 could be starters for Gibbs.

There were some familiar faces: Theismann, because the quarterbacks always come in early; receivers Art Monk and Ricky Thompson; linebacker Brad Dusek, trying to return from back surgery; guard Fred Dean, who is projected to take over for veteran Ron Saul and is trying to make a quick impression, and Terry Metcalf, wearing a Redskin uniform after so many years as a tormentor in Cardinal red and white.

Still, these first days of camp belong to the youngsters.

What the Redskins accomplish not only this season but in years to come will depend on the development of linemen like tackle Jerry Scanlan (6 foot 5, 270 pounds), who is expected to beat out veteran Terry Hermeling; guard Melvin Jones (6-2, 260), who will vie with rookie Russ Grimm (6-3, 250) for Jeff Williams' starting spot; defensive end Mat Mendenhall (6-6, 253), expected to take over Coy Bacon's defensive end position, and rookie end Dexter Manley (6-3, 240), who could become the club's new pass-rushing specialist.

And they keep getting bigger. Rookie tackle Allan Kennedy is a mere 6-7 and 268, a tad smaller than tackle Joe Jacoby (6-7 282), a free agent who might become the surprise of the camp. Pat Ogrin (6-5, 265) spent last year on injured reserve; now he will push Perry Brooks for a defensive tackle spot.

These are the fruits of Beathard's labors over the last two seasons. Since only one 1980 draft choice, Monk, would up making the roster last year, Gibbs actually is evaluating a double draft -- those picks from 1980 who spent last season on injured reserve plus the 1981 crop, the largest in team history even without No. 1 selection Mark May.

"You think they all can play but this is where you find out," Beathard said as he paced the sidelines. "We've got high hopes for them."

Expectations are high among team officials, after the youngsters' performances in the minicamps. It seems inevitable that the changeover from old to young, especially in the starting lineup, will occur before the end of the camp. But there is no way of telling yet if the rookies will become legitimate players in just six weeks. That's the reason this camp will remain interesting despite the heat and boredom of two-a-day workouts.

"This is an easy situation for me to work in," Gibbs said. "There has been nothing but cooperation from Bobby and Mr. Cooke (team owner Jack Kent Cooke). Even in the May negotiations, we agree. You'd like to have your No. 1 in camp, but you also have to have certain rules to follow."

Center Russ Grimm, the thirdround pick from Pittsburg, finally signed a contract . . . Beathard reported no progress in his talks with May. Another session is scheduled for Thursday . . . Cooke and his wife watched the lone practice today . . . Former Maryland kicker Mike Sochko, who is trying to make the roster, sprained an ankle jogging Tuesday and was on crutches today . . . Dusek has begun light jogging in his rehabilitation process . . . Ray Waddy, the cornerback who broke his leg last season, is also making good strides in his comeback attempt. He no longer limps as he works out with Dusek.