SAN DIEGO — Hide the women and children.

No, that's not right. Jim McMahon already has a wife, Nancy. And they have three children.

Nancy is a saint. She lives with McMahon. Every day.

Their kids are the joy of Jim McMahon's life. Golf is his favorite sport. Chicago is still his city of preference. And playing quarterback in the National Football League is his passion.

When football is not in season, McMahon can't get back to the privacy and creature comforts of his home fast enough. Located in the upscale Chicago suburb of Northbrook, McMahon's dream house features a racquetball court, two locker rooms, a swimming pool, a putting green, a sand bunker, a playground, a weight room and, a hot tub.

Ask McMahon what he misses most about the Midwest since he became a San Diego Charger and he will tell you: "The house . . . sleeping in my own bed."

The McMahons will return to Northbrook after the season.

So consider the women and children of "America's Finest City" safe. From Jim McMahon. For now.

Hide the owner.

Alex Spanos, the Chargers' chairman of the board-president, has a heart bigger than the San Joaquin Valley, where he used to drive a catering truck that serviced migrant workers. Spanos parlayed those early dollars into a large fortune by investing in California's No. 1 natural resource--real estate.

Now he can afford to be generous. But Spanos is tougher than third and 19. And his politics are conservative. The quarterback to whom he will pay $800,000 in this, the last, year of his contract, is about as tuned into Spanos' Republicans as the Democratic donkey.

If the questions about McMahon's arm strength and durability turn out to be legitimate this year, the Chargers will suffer, and Spanos will carefully find a way to channel his displeasure in the public print. He is good at that. McMahon will respond in kind.

If, on the other hand, the instant adrenaline boost McMahon has provided doesn't wear off, the Chargers and their improved defense have as good a chance as any team to win in the AFC West. They will start finding out Sunday when they play the Raiders in the Coliseum starting at 1 p.m.

And if that happens, McMahon will demand a sum of money starting in 1990 that will make Dan Fouts' last contract look like chump change.

So, no. Despite all the excitement of the moment, the voluble Spanos and the free-spirited McMahon will eventually be at one another. It is inevitable.