Joe Theismann smiles about it now. But two years ago, when he did "everything including beg" to persuade the Redskins to trade him away from Washington, his future in pro football hardly was a laughing matter to him or his family.

Back then, perhaps only Theismann, the eternal boy scout, thought he was a bona fide NFL quarterback.

But things have changed for the player once described by a writer as "the Golden Boy who will never be anything but a loser."

Theismann's critics -- and they were legion -- have been silenced this season. Once amused by his antics, rivals now volunteer praise. His teammates, once doubtful of his ability to lead, accept him now as a legitimate star.

It's taken him nine difficult, sometimes stormy years in pro football to reach a pinnacle where no one doubts his talents anymore and where he no longer is looking over his shoulder, wondering when his next benching will occur.

Theismann has had to produce a superior season to finally silence his detractors. Not since 1969, when Sonny Jurgensen had his last highly productive year, has a Washington quarterback turned in the kind of numbers Theismann is rolling up this season.

He is ending the 1970s with statistics that out-do Billy Kilmer at his best. His 2,301 passing yards, his 58 percent accuracy mark, his 17 touchdowns, his 11 interceptions -- all reflect an across-the-board consistency that establishes him among the league's best quarterbacks.

You have to go back to the late 1960s, when Jurgensen was throwing for 3,000-plus yards a season, to find a more potent Redskin passing game. But Jurgensen was laboring mostly on losing teams; what makes Theismann's season so significant is that Washington is winning and he is probably the player most responsible for that unexpected turn of events.

Theismann could gloat over what has happened in the first 14 games. But except for admitting that "I'm very proud of my accomplishments this season," he resists saying "I told you so."

"I've worked hard for what has happened," he said, "but I'm not going to be vindictive about it. I was talking to my wife about this the other night. This year means so much to me because, starting last February, I really committed myself to becoming better. It wasn't a life or death situation, but I wanted to get a good foundation so I could react in games instead of thinking."

Jurgensen, from his perch as a television commentator and revered local sports hero, has watched Theismann's development with particular interest. He points to a new-found ability to finally stay away "from going for the home run, trying to do it all himself," as the turning point in Theismann's career.

"He's always had the athletic ability," Jurgensen said. "Now he has the maturity and the consistency. They've given him a structure and told him what they wanted and he's stayed inside it.

"He really hasn't had any bad games this season. He's been remarkably steady, something he wasn't before. You just can't go for the home run all the time.You've got to take what the other team gives you.

"He's also improved in the two-minute offense. He's made himself use the short pass and pick away. He's had the right discipline you need at that moment."

If Theismann hadn't realized already the true merits of his present style, the point was driven home for good last week against Green Bay. In past seasons, if he had been trailing, 21-7, at the half, he would have come out tossing 40-yard bombs. This time, he calmly pecked away at the Packers and ultimately got touchdowns off two short throws that wound up substantial gainers.

"That was my quarterbacking utopia," Theismann said. "I always was trying to do everyone's job. Here I just did mine and lo and behold, two guys (John McDaniel and John Riggins) turned little passes into something a lot bigger. It was a nice feeling."

It also was a nice feeling for offensive coordinator Joe Walton, Theismann's football guru. When most thought the Redskins were taking a tremendous chance committing themselves to Theismann this season, Walton patiently programmed his quarterback, starting with those February meetings and continuing even this late in the schedule.

"I hate to say it." Theismann said, "but he spoon feeds me hunks of stuff at a time. I absorb it and then go from there.

"Now I think I've reached a peak where I'll never go back to my bad habits again. Every time I feel myself slipping, I go over my steps, my setup, things like that, to make sure I don't go back to much."

Remarkably, Theismann has won this season without producing one of his best five passing days as a pro. And he's won by relying heavily on short passes, which help the percentages but not the total yardage. Yet he's loosened defenses so much with this controlled attack that points and victories have resulted.

"The way our offense is structured, the way we need to play to win, we couldn't have done it without Joe playing the way he has," Coach Jack Pardee said. "Is he our most valuable player? Well, I'd hate to think about where we'd be without him."

Compliments like that make this season so unique for Theismann. He is even reading newspapers again.

"In this job, where the competition is so keen, the first thing you want is your teammate's respect," he said. "I hope I have that now.

"Secondly, it is good to know your rivals think well of you. They know how tough or easy it was before. You like to make an impact on them and get their respect, too.

"If you can stand the really bad times and pay the price, it makes all this a little more sweeter. You get more satisfaction out of it."

Yet Theismann admits he has wondered what his career would be like if Walton had come along five years ago and given him the opportunity to develop.

"I don't know if I had the maturity at that point to accept someone's else's view like I have now," he said. "Joe has been tough on me, he's pushed me and I guess that is what I needed.

"The point I have to remember is that I'm in better shape physically right now (through weight lifting) than I was five years ago. And I'm much better prepared mentally."

So, at age 30, Theismann is just beginning what promises to be a fine NFL career. Both Pardee and Jurgensen see no reason why he can't get better since this actually is only his first full-time season.

Theismann, whose carefully constructed image of a cheerful, loquacious, be-sweet-to-everyone human belies his fiercely competitive nature, put it more bluntly.

"I can be as good as anyone in the game," he said, some of the old Theismann showing through.

Then he paused and the new Theismann took over.

"But only because of the people around me," he added. "the quarterback may be in the middle, but it is what's around him that counts."

NOTES: Pardee reluctantly has decided to root for Dallas today against Philadelphia, "as hard as that is going to be to do." A Cowboy win would keep the Redskins in the running for the NFC East title . . . Halfback Ike Forte is the father of a baby girl.