Of course, this was not one of those prototypical Stone Age monsters, who stand 6-feet-5 or 6-6 and weigh somewhere between 260 pounds and Andre the Giant.
The Midway Monster for the '80s was a quarterback, of all things. He was an Irish Catholic maverick from Brigham Young, of all places, who mooned aircraft and taunted the commissioner with headbands, of all things.
This was a guy who would wear dark glasses at 4 a.m., if anyone could find him at 4 a.m. No one could Monday, when he had been scheduled as a guest on a couple of those network chat fests.
But Jim McMahon, Mr. Punk, marches to a different synthesizer than everyone else.
What the Chargers hope, of course, is that McMahon can march them into playoff contention in the American Football Conference's Western Division for the first time since 1982, when no one outside of a few construction foremen and Bob Hope had heard of Alex Spanos.
McMahon really does have people fired up. The Chargers have been selling season tickets at the rate of 200 a day since the trade was announced last Friday. The public address department is fielding media requests in a volume reminiscent of the days of Air Coryell. Folks are daring to use the word "playoffs" without fear of ridicule.
Indeed, the acquisition of McMahon is the most interesting thing to happen to the Chargers in years. It remains to be seen whether this is the best thing to happen since Don Coryell came down off Mt. Helix in 1978 to inspire those glory years, but it is the most interesting.
Interest manifested itself in television ratings last Saturday night, when McMahon made his Charger debut with that four-play cameo against the Bears. Of televisions in use in San Diego, 52% were tuned to the Chargers. Not bad for a seemingly meaningless exhibition exercise.
You don't suppose McMahon's presence had anything to do with that? Naw.
Surely, there was more of that same anticipation Wednesday night, when McMahon came out of his crash course in "Charger Playbook" to make his first start here against the 49ers.
To analyze McMahon's role in what was eventually a 17-14 Charger loss, it is important to understand that Charger playbook. This is not an offense in which running plays are footnotes and passing plays are chapters. This is an offense designed more with safeguards in mind than bombs, one which hopes to set up the pass with the run rather than vice versa.
Forget the days when a Charger quarterback throws 40 times for 350 yards. Given optimum conditions, meaning the game is close, McMahon will rarely throw more than 25 times a game. His value will not be measurable in terms of passing statistics.
What the Chargers ask of Jim McMahon is that he provide leadership and stability. They want him to be a presence in the huddle, on the sideline, in the locker room, at practice and even on the airplane. He has been where everyone else wants to go, which is to say the Super Bowl.
This offensive philosophy is not exactly new to McMahon. This was the way the Bears did it, and it worked rather well for them. The most he ever threw in one game for Chicago was 42 times, averaging much closer to 20 in an offense that was always near the National Football League lead in rushing.
So what McMahon did Wednesday night, essentially, was run the offense. He was splendid in the first period, controlling the ball and establishing field position. That the 49ers were scoreless through that first period was as attributable to the Charger offense as it was to the defense. The Chargers controlled the ball for 13:03 of the game's first 16:39.
And the score was 0-0.
This is how the Chargers are going to have to do things to be successful. Protect and control the ball and put the defense, which is quite good, in the best position possible to force the other team to self-destruct.
These are things Jim McMahon does well.
In fact, he did them well Wednesday until he got a little impatient inside the two-minute mark at the end of the half and floated a pass long to Dana Brinson. Ronnie Lott picked it off and set up the game's first touchdown.
After a brief appearance at the start of the second half, his work was finished for the night. He played as well as, or maybe slightly better than, might be expected of a guy with only three days of taking snaps with a new team.
While his passing statistics are not the measure of what he is being asked to contribute, surely he was less than pleased with seven completions in 13 attempts for 26 yards. But the passing game will be the last to come.
Thus, to assess McMahon's first start, it would be fair to say he was on schedule though not necessarily on target.
This patient offense will be patient with Jim McMahon, because this erstwhile Monster of the Midway could well be a rather monstrous presence in Mission Valley . . . and the AFC West.