The bar had been filling up gradually for two hours. Cigarette smoke was beginning to cloud the lights. The crowd was restless. Finally, someone began with a microphone switch.

"Is it on?" a voice boomed over the public-address system, answering its own question.

"Ladies and gentlemen," the voice continued, "we are looking for men weighing 150 pounds who want to box. We are looking for a lady boxer who weighs 110 pounds or thereabouts. Anyone who wants to box, step up and we weigh you and sign you up. Prizes for everyone."

Thus began another evening of free-wheeling, free-swinging and bizarre entertainment at a nightclub bar here called Bogart's which once a week cordially invites patrons to slug it out against each other.

At least three our four other Arizona bars do the same. A boxing ring is set up on the dance floor, people in the crowd sign waivers absolving the club of responsibility for injuries, gloves and mouthpieces are provided and the result is kind of a cross between "The Gong Show," "Rocky" and roller derby.

People fight barefoot. People fight wearing jeans. People fight their friends. The crowd cheers them on. The bouts are three rounds, but many are stopped in the first or second. Winners usually receive $10, losers $5 or two free drinks. No doctors are present, no physical examinations given. Although such bouts are illegal in nearly every other state, they are legal in Arizona - to the dismay of State Athletic Commission.

"We've tried to stop, but we went to the attorney general's office and they said there's nothing we can do," said Mike Quihuis, one of the three commissioners. "I went to see one of the barroom fights once and it was horrible. It's a disgrace to boxing."

Quihuis is not alone in this sentiments. The Tucson Citizens editorialized against the bouts after printing a story on safety hazards. The Amateur Athletic Union has barred from the shows any boxer who wishes to remain amateur. Doctors have noted that a boxer might be seriously injured, with no trained medical personnel present to check on a fighter's condition.

Yet the bouts continue in Phoenix and Tucson. When the athletic commission asked the courts to end the fights as a "public nuisance," the courts refused.

"Everything we do is legal," said Joe Bono, general manager of Bogart's. "If I could afford to hire a doctor, I would. But that would cost at least $100 a night. When people say the boxers can get hurt, I say they can get hurt at a fight run by the commission, too. In fact, I thing those guys would have more of a chance getting hurt, because they know how to hit. Most of the people here don't know how to hit."

(That is obvious. Many of the fighters seem to be from "The Three Stooges" school of combat. They flail away, alternately showing and grabbing each other. The wonder, one observer noted, is not that people will make such fools of themselves but that others will pay to watch.

Bogart's charge $2 general admission and $3 for a ringside seat. Most of the money, however, comes from liquor sales. Four nights a week, the 400-seat club has live rock and disco music. But Tuesday Night Boxing is more profitable than Saturday Night Fever.

"The boxing crowd drinks more," Bono said. "The people are macho types. The cover charge hardly covers expenses. It costs me $150 to set up the ring and I spend another $150 for advertising. I make the money on the bar."

Even people who detest the fights can see why they are popular.

Quihuis: "There are not many other boxing shows in town, it only costs $2 or $3, and people can sit there and drink to their hearts' content. I went one night and it was horrible. People stinking drunk got up there and started fighting. One of these days, somebody's going to get killed."

Bono' reply: "I haven't seen anybody getting hurt. If it's an obvious mismatch, we stop the fight."

It can be argued that barroom boxing is a natural extension of the brawls that once enlivened Arizona's saloons. The hum of air-conditioners may have replaced the sound of Main Street gunfights, but there still is a bit of Wild West left here in the desert.

A popular activity among the young, for example, is driving to remote spots for raucous beer blasts called "Boondockers." Many pickup trucks sport branding irons painted on the doors. String ties are as fashionable as ever.

No one seems to know exactly how the barroom bouts began, but they have been staged off and on in Phoenix and Tucson for quite some time. Old-timers recall organized bareknuckle fights in dance halls. The present concept, Bono thinks, was originated by promoters who moved in after barroom boxing was outlawed in Colorado.

After gaining popularity in Phoenix, the bouts moved to Tucson last summer when one tavern began holding "grudge" matches. When it went out of business, Bono took over. A 45-year-old immgrant from Albania, he moved to Tucson last year after his sister-in-law bought Bogart's.

In the beginning, the fights were mostly for laughs. Someone would utter a discouraging word in describing a relative or friend and they would end up challenging each other. They used heavily paddled 16-ounce gloves (most pros use eight or 10-ouncers), and no monetary prizes were awarded.

But soon, a number of things happened to make the fights less laughable.

First, the supply of boxers who wanted to settle grudges in bar began drying up. For many, one turn inside the 14-by-14-foot ring - with little room to run away - was enough.

Second, boxers who were successful started coming back week after week to prove it, taking on all challengers and beating most.

Third, amateur clubs, such as the one sponsored by the Police Athletic League, disassociated themselves from the bouts after first taking a somewhat benevolent attitude.

And, finally, more and more attention was focused on the safety problems. Two Tucson Citizen reporters, Dave Petruska and Mike Larkin, wrote a story saying some boxers drank alcohol before bouts, and that others fought twice a night.

Bogart's no longer advertises in the Citizen, buying radio time, instead. Bono has introduced the cash prizes to encourage more boxers, and is convinced the bouts will survive.

"This place was completely full for months and months," Bono said. "The fire marshal had to come out and check us over to make sure we didn't have too many people in here."

It appears certain the fights will continue disturbing the sleep of their detractors for a while. A gap in Arizona law permits them in counties with a population of 125,000 or more.