You have seen this character Jim McMahon before, in another athletic life. Some of you saw a little of him in the '30s and '40s, in Sammy Baugh. Another generation saw lots of him in Bobby Layne in the '50s. Washingtonians surely have detected a touch of Sonny Jurgensen in his on-the-field arrogance.

Thank goodness.

For a while there, it seemed as though all the fine NFL quarterbacks were going to be pretty-boy clones who pitched lines of clothing more than they pitched footballs.

"I've never known a great quarterback who was normal," said John Madden, meaning that as a compliment both to the player and to the position.

McMahon clearly ain't normal, as you undoubtedly have noticed this season and this week. A normal guy does not show off his acupuncturist's handiwork to a helicopter pilot intruding on his outdoor office, when the acupuncture happens to be where it was for McMahon.

Whether the butt of controversy is a great quarterback will be determined, in part, by what he and the Bears do here against the Patriots in Super Bowl XX Sunday.

Jurgensen was fond of saying that a man really couldn't consider himself a legitimate pro quarterback until he told the head coach to go to hell at a vital point in a big game and improvised a play himself. That play had to defy convention -- and work.

McMahon did exactly that against the Rams in the NFC title game two weeks ago in Chicago. Coach Mike Ditka sent in a draw play; McMahon opted for a sprintout to the left that resulted in a wonderful off-balance spiral, a 22-yard touchdown pass to Willie Gault.

"On third and 17," said Jim Finks, the former Bears executive who drafted him, "I'd put my money on McMahon anytime. He's not afraid to put his skills on the line when the chips are down.

"He wants that hog (football)."

McMahon reported to the Bears his rookie year, from Brigham Young, with a beer in his hand. He exchanges affectionate helmet slaps with offensive linemen after touchdowns but cusses his blockers grandly after missed assignments.

Remind you of anyone?

"Bobby Layne," said Ditka.

"And (Norm) Van Brocklin and (Billy) Kilmer," said Finks.

"When Bobby said block, you blocked," his former Detroit Lions teammate, Yale Lary, said. "When Bobby said drink, you drank."

In a fit of near-panic, because some ill-tempered lineman were pawing at his body, Jurgensen once threw a pass behind his back -- and completed it.

"McMahon can throw left-handed if he has to," Finks said. "And who else could throw those kind of tight spirals wearing a glove, as Jim did (against the Giants and Rams)?"

For the Redskins, Baugh once put a football between the eyes of an especially rude defensive lineman. Knocked him cold. Only face masks prohibit McMahon from a similar tactic.

McMahon would have been welcomed with open arms, and wallets, by the Over The Hill Gang Redskins. They would buy several beers for anyone who tweaked authority the way McMahon did Commissioner Pete Rozelle.

In their own sly ways, many early-'70s Redskins bucked the league-mandated code of game-day attire, that uniform pants had to be a uniform length, that socks had to be a certain style, etc.

Roy Jefferson's game pants looked more like walking shorts. He must have chuckled over McMahon lettering his headband "Rozelle" after the commissioner fined him $5,000 for wearing one advertising a shoe company.

Almost assuredly, McMahon was being paid by that shoe company. In that way, there is more than a tiny bit of two Joes, Theismann and Montana, in this unique Jim.

"Maybe I'll wear a label on my butt, too," he told the Chicago Tribune's Bob Verdi. "Made in Japan."

"Gotta let players have an identity these days," Ditka said. "I'm not running a police state. You must have a flexibility that wasn't necessary 20 years ago."

Without being too rigid, exceptional NFL quarterbacks seem to fall into three basic groups. One includes the hell raisers, whom we've already mentioned, and another is made up of clean livers. The latter is a lineage that includes Sid Luckman, Otto Graham, Fran Tarkenton and Roger Staubach.

Former Redskin Diron Talbert joked that if a rushman could get close enough to yell an expletive at Staubach or Tarkenton, it was as good as a sack.

The third breed of top-flight quarterback is the smoothie who generates at least as much income from nonfootball performances.

Happily, McMahon seems more a football descendant of the '50s than the '80s, even though his hair and clothes suggest otherwise. Besides, when he intrudes into our lives too much off the field, we can perform acupuncture of a sort on him.

We can turn him off.

Football people tolerate the McMahons so long as they produce championships. Their major problem with McMahon is his style during games, not after them. His reckless attitude is inspirational to teammates, but also dangerous.

"My only question about him is durability," said Finks. "He always finishes the game, but then he misses three or four days of practice the next week.

"Maybe he's not a fast healer. To my mind, that's the only thing that's gonna keep him out of the Hall of Fame."