They resembled your everyday neighborhood flag football team dressed out in assorted sweatshirts, shorts and hats. Except the left tackle was 6 feet 7 and 295 pounds and the quarterback looked just like Joe Theismann.

Actually, that was Joe Theismann. And Joe Jacoby, Dave Butz and 35 other Redskins. They returned to the sandlots last week to work out two days at a Virginia high school, trying their best to stay in condition and keep up their morale in the face of what could be a long and costly strike.

The early days of the strike revealed a lot about this team and about many of its players. There was a concerted effort to remain in shape and to stay unified. But the players also know the longer the strike lasts, the harder it will be to accomplish either goal.

"Beyond a couple of weeks," said Jacoby, "you start to lose your feel for contact that you've built up since training camp. Then it will be almost like starting over again. You'd really need some time to get ready, although I'm sure we're aren't going to have more than a week."

At Redskin Park, Coach Joe Gibbs could only sit and fret. "It's only conjecture," he said, "but it will be tough for them to stay in great shape. It's up to the individual. Some will push, some won't. If they keep practicing and working on the passing game, it will help their timing. But they can't come back in game shape, no way. If they are out less than a month, I think we can have a regular week's practice and be okay. Beyond that, I don't know."

The longer the strike lasts, the more difficult it probably will be to get a large turnout at the workouts. "You have to start wondering what's the use," Jacoby said. "Right now, it's easy to push yourself. After a while, you can lose your enthusiasm, thinking the season is over."

The players are being prodded by Mark Murphy, the team's player representative, and by Russ Grimm, the alternate. Grimm is playing a major role after the former alternate, Dallas Hickman, was cut three weeks ago.

With Murphy participating in negotiations, Grimm has carried the burden of organizing the workouts and keeping the players informed. From all indications, he has accomplished that, although after giving 10 interviews the first day of the strike, he was ready to return all responsibilities to Murphy.

Then there is Theismann, perhaps the most intriguing story among the Redskins. In 1974, when the union last struck, Theismann was a rookie, having signed with the Redskins after three years in the Canadian Football League. Washington was among the league's most militant teams, yet Theismann crossed the picket line, a decision that affected his relationship with his teammates for years.

"It was very, very uncomfortable after everyone came back," Theismann said. "I was the black sheep of the family. I was shut out, alienated from all but five or six players. It was a painful time. I never fit in after that. The veterans resented me from then on. I paid a heavy price for a lot of years.

"But all I cared for then was Joe Theismann. I was going to take care of myself first. I wasn't a member of the union, I was a rookie, so I had nothing to gain by sitting out. That's what I thought. I wanted to make the team and I couldn't do that sitting on the outside. I really had no decision to make.

" . . . What I did then was wrong. It was self-serving. You have to care about yourself individually, but in a situation like this, when a lot of people can benefit, you have to look at the big picture, too. The most important thing to me is that the Washington Redskins stay strong when it's over. I want us to come out of this unified."

Theismann still is not a gung-ho union man. He realizes that the older players who remember 1974 are watching closely, seeing if he stays out or if he ultimately will return to the team before the strike is over.

"I probably have surprised some people already," he said. "But I said I would go along with the majority of the team this time and I did. I said I would go in in 1974 and I did. I stick to my word."

Theismann also has not remained silent about the strike. He has assumed a leadership role during the player workouts, organizing the offense and using old game-plan sheets to call plays. ("How would you want to coach a player like me?" he asks.) Off the field, he has been especially outspoken in his criticism of Jack Donlan, executive director of the NFL Management Council. "I'm not an advocate of percentage of the gross and I've said that right along," Theismann said. "I don't think the owners are our enemies. Now that we've changed from percentage of the gross to television revenues, I like our proposal much better. They (the owners) have a bonanza of money. We are looking for a way to share in that bonanza. And they shouldn't concern themselves with how we decide to divide up our share.

"Give us unrestricted free agency without compensation and you'd see a lot of players go for it. Make that part of a compromise. I'd also like to see some sort of severance pay built into the contract. It might help guys make the adjustment better from football to society. Maybe you wouldn't see so many stories about guys turning to drugs. But who is doing their negotiating? Why don't they give Jack Donlan enough authority to sit down and really talk, or is he really calling the shots?"

By sitting out, Theismann loses one-sixteenth of his $300,000 salary for every game he misses. Only John Riggins among the Redskins will suffer a larger financial loss during the strike. But Theismann can always fall back on a variety of outside interests, including two restaurants.

"We're going to try to help out anyone who needs it by finding them a job at the restaurant," he said. "I've also got an extra room at the house. No Redskin is going to go under because of this strike, not if we can do something about it."