Joe Theismann worked out extensively yesterday at Redskin Park and will start at quarterback Sunday against San Diego unless he aggravates his injured hamstring.

Theismann said his leg felt "pretty good" after practice, his first lengthy test since he reinjured the leg 11 days ago against Dallas.

"It still hurts some; I still know the hamstring's there," Theismann said.

"But I think I'll be okay. I feel good about it right now."

Coach Jack Pardee said that, as a precaution, backup Mike Kruczek will continue to work out some with the first string. But Pardee said he was encouraged by Theismann's progress.

"He had a pretty good workout," Pardee said. "We'll watch him closely and if we think he's ready, he'll start.

"If it doesn't bother him after working on it, we'll go with him. That's what we are hoping for at this point."

Although Theismann's hamstring will not be 100 percent before the end of the season, he has much more flexibility than he did a week ago, when the injury was healing very slowly.

Pardee realizes that starting Theismann will be risky, since he will not be as mobile as normal, especially against a San Diego defense that leads the NFL in sacks.

But the Redskins also feel they don't have a good chance of beating the Chargers unless they can employ the full scope of their offense. And with Kruczek at quarterback, Pardee has severly limited his attack.

"We've got to score points in this game to win," Pardee said. "We can't expect to get them in a low-scoring contest. That is unrealistic. So we need more touchdowns than we've been getting. We need to use everything we have, and with Joe in there, we can."

Pardee says he is convinced the offense, which has scored only 51 points in the last five weeks, is ready to break out, as long as Theismann can hold up and provide some passing yardage. The Redskins have struggled through the air ever since Theismann was first injured, against Philadelphia three weeks ago.

What perturbs Pardee is that his team has wasted two outstanding efforts by his defense, which played well enough for the club to win against Dallas and Atlanta.

"We are finally where we want to be on defense," Pardee said. "We are doing things now that we've been wanting to do all along, but couldn't, because of the injuries we had earlier in the season."

Atlanta and DALLAS WERE TWO OF THE NFL's highest scoring teams, but managed only 24 points against Washington. One of those touchdowns came on an interception return and another was set up by a punt return to the eight.

Perhaps the biggest improvement by the defense has been its ability to stop the run. Although the front four has not improved its pass rush, it is tackling better, one reason the Cowboys were limited to 115 yards on the ground and Atlanta 131.

"Now we have been able to get people into second-and-long and third-and-long situations," Pardee said, "which has been our aim right along. Once we get teams to pass on us, we like our chances.

"I know the front four is old, but otherwise, this is a pretty young defense. We are now showing that we are maturing, especially with people like Monte Coleman, Neal Olkewicz, Rich Milot and Jeris White, who was new this year.

"We aren't that far away from being really solid on defense. We just need one jof our young guys to come through for us on the line next year and I think we'll be okay."

Although Pardee still believes strongly in multiple substitution on defense, injuries have begun to limit his flexibility the last few weeks. The Redskins have been shuffling in fewer people and playing better. Earlier in the season, a few of the veterans called for fewer substitutions, saying the club would profit by more stability.

"We'd like to use more people than we have been," Pardee said, "but with Pete Wysocki and Perry Brooks hurt, for example, we don't have as many people available. It means a guy like Monte Coleman has to play longer, but he's improving all the time, too, so it's helping both him and the team.

"Still, we've been able to go full speed much better these last few weeks. We can use all the defenses we've been wanting to use instead of being hurt using multiple defenses and multiple substitutions.

"We can become much more agressive.We can blitz and do things that will disrupt the other team."

That aggressiveness has led to an increase in forced turnovers, a specialty of the Redskins last year. Dallas gave away the ball six times and Atlanta nearly had a half-dozen passes intercepted.

"We are going to have to be very alert this week," Pardee said. "Teams that have beaten the Chargers have forced turnovers. If you don't, they can kill you."

Pardee is concerned about Lemar Parrish, who has sore ribs. Parrish has played before with sore ribs this season but if he doesn't Sunday, White will replace him . . . Linebacker Brad Dusek returned to practice after spending time in traction at Sibley Hospital . . . Coy Bacon missed practice with a cold.