LAS VEGAS, April 9 – Floyd Mayweather Jr. kept his head while all around him others were losing theirs. While he tried to recover from a leg-numbing shot to the family jewels, one of his family’s non-jewels touched off a ring riot, during which Zab Judah knocked down the wrong Mayweather, a Metro police officer standing on the ring apron patted his holstered gun and warned a mob of Judah supporters “don’t you come up here” (they didn’t) and, when it was finally over, there was Don King arguing that you have to obey rules “for the integrity of the sport.”

It was so bizarre that, for the moment, even the IRS isn’t getting its inevitable due.

That’s because after the riot, the Nevada State Athletic Commission withheld the purses of Mayweather ($5 million) and Judah ($250,000), pending a hearing this Thursday morning.

Almost lost in the confusion was the fact that while Mayweather dominated Judah over 12 rounds at the Thomas & Mack Arena, his performance was, as Budd Schulberg noted, “disappointing” and even if Pretty Boy is currently the best in the world he made no compelling argument that he was one of the greatest in history.

The fight is not over. There remains a chance that Mayweather’s unanimous decision could be overturned Thursday by the commission. Theoretically, the five-man board, after viewing films of the fight and ring-filling brawl, could disqualify Mayweather for his trainer, Uncle Roger, entering the ring or disqualify Judah for flagrant fouling or call it a no-contest and, like the Judah camp, ask for a rematch. There seems no legitimate reason to watch this family feud again. Mayweather is clearly superior to Judah. He had some awkward moments early, perhaps before he adjusted to Judah’s southpaw style, perhaps as he said, to take his time and let the former undisputed welterweight champion shoot his load.

Most reasonably, Nevada will let the undefeated Floyd Mayweather Jr. keep his 36th  victory, suspend Uncle Roger for, in the words of incoming executive director Keith Kizer, “a long time.” Kizer, the assistant state attorney general who currently is the commission’s legal counsel, takes over May 13 when Marc Ratner joins the peaceful Ultimate Fighting Championship.

“It may be a long time before Roger Mayweather works in a Nevada corner again,” said Kizer of the volatile former two-time champion who was involved in a couple of extracurricular scrapes (his trainer, Jesse Reid, once charged into the ring and went after Julio Cesar Chavez, and once Mayweather decked Lou Duva in a post-fight mismatch).

Kizer said the commission would study the films to see if “others are culpable.” These include Yoel Judah, the fighter’s father and trainer, who went after Roger Mayweather for choking his son – that’s not quite a mismatch, Yoel Judah-Roger Mayweather, because Yoel was a former world kickboxing champion.

Also, Leonard Ellerbe, Mayweather’s conditioning coach and close friend, entered the ring and, for his trouble, was hit by a Zab Judah left hand. Afterwards, Zab circled the field and came behind Roger Mayweather and hit him with a right hand to the back of the neck – the same punch he hit Floyd Jr. with in a foul combination started by the left hook to the cup. Roger Mayweather went down, said Richard Hofer of Sports Illustrated, “so I gave Zab the round, 10-8.”

Zab Judah said he hit no one in the ring, but a Los Angeles Daily News photographer captured the images of the punches to Ellerbe and Roger Mayweather.

Judah also said the low blow was not purposeful. “I’m not a dirty fighter,” he said. “It’s not my style.”

But Floyd Mayweather said earlier in the week, he was warned by his Uncle Roger that Judah would resort to dirty tactics in desperation. “We had a talk and Roger said [Zab] didn’t really want to fight me.”

By the end of the tenth round, Judah was bleeding from nose and mouth, his right eye was swollen, and he was taking a beating to the body. At least he didn’t bite Mayweather’s ears.

“I don’t know if [Zab] did it deliberately,” Mayweather said in the ring.

Before the fight resumed with the final seconds of the tenth round, while Referee Richard Steele waited for the battalion of security to leave, Mayweather went over to Judah to touch gloves. Was that, he was asked after the press conference, a sign that he believed the low blow was accidental?

“No,” he snapped, “that meant ‘let’s keep it clean.’ He was tired. I was breaking him down.”

He maintained, quite reasonably it seemed, that if not for the five-minute delay, bought first by the low blow which came to close to ten minutes with the melee as many in the crowd of 15,170 menacingly approached the ring, Judah wouldn’t have been able to recuperate from the beating he was taken.

“I wasn’t even hitting him hard yet,” said Mayweather.

From the neutrality of the corner where he waited for the feeling to return to his left leg, Mayweather couldn’t see what was happening. All of a sudden, he said, “There was a thousand people in the ring.”

His uncle started it by rushing in as Steele was signaling the timekeeper to stop the clock for the wounded fighter to take up to five minutes if needed. Roger grabbed Zab by the neck, Yoel Judah flew into the ring and fans and cornermen entered, along with enough Metro cops and arena security to start another desert war.

King maintained that “as soon as” Roger Mayweather entered the ring, the bout should have ended in a disqualification. “It’s the rules,” he argued with HBO commentator Larry Merchant.

“Yeah, we must follow rules,” Merchant told King, his tone dripping with irony.

King argued that once, Erik Morales’s brother Diego knocked out an opponent in Tijuana, and was disqualified when his father and trainer prematurely entered the ring – as if Tijuana “rules” applied to Nevada.

“In any commission in the world, that’s a disqualification,” said King.

In fact, Nevada Rules, according to both Ratner and Kizer, say that a disqualification is up to the discretion of the referee.

“It’s not automatic,” said Ratner. “We’re given leeway to take other factors into consideration.”

One factor might have been the reaction of the crowd to any kind of DQ.

“It would’ve been a wild, wild scene,” said Ratner.

Steele, after consulting with Ratner and Skip Avansino, said he allowed the fight to continue in deference to the fans.

“I worked with the commission and we felt a disqualification wasn’t warranted,” he told Kevin Iole of the Las Vegas Review-Journal. “Two fighters fought their hearts out and it didn’t seem right to stop it because of a cornerman. And you have to think of the fans. You want to give them their money’s worth and they would have felt cheated if there was a disqualification.”

“I think we acted appropriately,” said Ratner, “and let the fight continue.”

“Nevada can do whatever they want to do,” said King. “For the integrity of the sport, you have to disqualify Mayweather for what his uncle did.”

Floyd Jr. ridiculed King’s sentiments. “Everyone knows Don King has been a crook for years,” he said, “continuously stealing fighters’ money. He’s a dirty promoter and he shouldn’t be in the sport of boxing.”

King called Mayweather’s comments “sour grapes.”

“Floyd is attacking now, I won’t even dignify his comments,” he said.

After the fight resumed, Mayweather said he was out of sync and, with Ellerbee now directing his corner in the absence of Uncle Roger, decided to just box his way to the obvious unanimous decision.

Judge Glen Hamada, who should be retired before he starts a riot somewhere with his nutty scorecards, gave Judah only the 12th and final round on a 119-109 scorecard. Jerry Roth also gave Judah the first two rounds on a 117-113 card and, in complete agreement with my own view, Dave Moretti gave Judah the first, second, fourth and 12th rounds.

The dominance of Mayweather, however, could be seen in the CompuBox stats. Judah threw a total of 444 punches, 40 more than Mayweather did, but landed only 82, or 18 percent. Mayweather landed 188 of 404 for 47 percent – and this after the slow start.

“I knew Zab was a frontrunner,” said Mayweather. “He’s strong in the first six rounds and then he grows fatigued.”

He said he followed the “game plan” to slowly “break him down” and had it not been for the tenth-round delay would have been able to finish the job. But Carlos Baldomir, a journeyman that HBO decided was not good competitive enough to face Mayweather, hurt Judah badly in the seventh round of  a clear unanimous decision in January to take the 147-pound title. Judah’s chin is not regarded as major league, so Mayweather’s inability to “break it down” quickly might indicate the former 130-pound, 135-pound and 140-pound titlist will have trouble in future welterweight battles.

But even Judah expressed admiration for Mayweather’s defensive skills and had no arguments with the decision. “I had his number early on, but he’s highly defensive,” he said. “Mayweather’s a good fighter. He’s very quick. I make no excuses. He was the better man tonight. It was a good fight.”

The Thomas & Mack was a couple of thousand shy of a sellout, but the large and loud greeting given Mayweather may be an indication that a noncompetitive fight – as a rematch with Judah figures to be – would still be as marketable as say promoter Bob Arum’s dream of a Mayweather showdown with the tough WBO welterweight strap-holder, Antonio Margarito, or the former champion, Sugar Shane Mosley.

Mayweather may now be at the stage, at age 29, of being so good that fans will want to watch him no matter the opponent. He entered the ring as the “challenger” – the IBFelons, following its own rules for the integrity of the game, allowed King’s fighter to keep its strap despite the loss to Baldomir since the Argentine refused to pay extortion in the form of sanctioning fees (leaving the title vacant, thus not being able to collect its pound of flesh from last night’s exercise, would not have been an option) – wearing a red robe with white fur trim.

“It looks like he got his robe off some sidewalk Santa Claus,” said Norm Frauenheim, the Arizona Republic’s astute boxing writer.

The fight started very cautiously. Judah’s right hand jabs were keeping Mayweather off and one second-round rush by Pretty Boy resulted in his walking into a right hook to the chin. But starting in the fifth round, Mayweather started landing meaningful lead rights, to body and head. He was not throwing combinations early, but he gradually increased his output from two-punch exactas to multi-blow medleys.

In the ninth round, Judah acknowledged a hard lead right hand with a nod of the head. They were talking to each other. “We’re from the same street,” said Mayweather. “He was calling me bitch and I was calling him bitch.”

Early in the tenth round, Maweather was so much in control he fired six straight left hands. Very few boxers have been able to throw one-handed combinations the way Mayweather can. The end was near. In effect, Judah said, “Balls.”

PENTHOUSE: Marc Ratner and the Nevada commission for saving my life – and perhaps a few others – by not disqualifying Mayweather for the indiscretions of his uncle. Danger was in the air as the crowd pressed close to the ring during the riot inside. The decision to continue the fight – there’s always the option of later ruling on disqualifications etc. – was a settling factor. Don King and others argued that the melee would not have spread outside the ring. Someone said that both the Mayweather and Judah contingents in the arena wouldn’t have been able to tell themselves apart.

Maybe, but this was not only about rooting interests going berserk. What about the folks who laid 5-1 on Mayweather and would have lost their bets on a DQ? Or those who bet the “go”? There was a lot more at stake than simple fan interest.

But again, Ratner and his crew were up to the task. Keith Kizer, his hand-recommended successor, said he was joking with Ratner recently about the outgoing executive director having to go through such mad scenes as “Fan Man” (when an idiot parajumped into the ring during the second Riddick Bowe-Evander Holyfield fight) and the Bites Heard Round the World (when Mike Tyson made dinner of Holyfield’s ears).

“I told him he’d probably have smooth sailing from now on,” said Kizer.

Now the executive director in waiting is hoping that the commission meeting Thursday,and any subsequent hearings can be cleared up before Ratner leaves.

OUTHOUSE: Don King, for arguing in favor of following rules “for the integrity of the sport.” Please. Even when the rules were explained to him, that Nevada doesn’t automatically disqualify a boxer if a cornerman illegally enters the ring, the Con King said “Nevada will do what Nevada will do,” but insisted that “has to be a disqualification.”

He said “I don’t give a damn” what the IBF will rule. Hey, when Judah lost to Baldomir, the New Jersey crime family said he was still champion. Now that Judah has lost two in a row, they’ll probably make him their champion for life.

DIS AND THAT: With the likelihood that Roger Mayweather will be suspended for a long while, Floyd Jr. will need another head cornerman. There seems little doubt that he will continue to say “uncle.” He said he had “total commitment” to his uncle, no matter what Nevada rules, and Roger will be his main man in the gym. Of course, he could bring his father, Floyd Sr., back, except that his most wished-for fight is a showdown with Oscar De La Hoya – trained by Floyd Sr….Juan Diaz, in a wonderful though somewhat one-sided 12-round fight, returned from a long layoff to outpoint previously undefeated Jose Cotto, older brother of Miguel, in defense of the WBA lightweight strap. Cotto threw an amazing 1403 punches over the 12 rounds, but landed only 192, or 14 percent. Diaz was much more accurate, landing 295 of 918, 32 percent. In a wild, toe-to-toe final round, they combined for 282 punches, according to CompuBox….Diaz said he next wanted either Diego Corrales or Jose Luis Castillo after their rubber match June 3, now set for Las Vegas, to “unify.” Problem is Corrales and Castillo are both moving up to 140 pounds afterwards….In what was an obvious mismatch as soon as they took off their robes and stood together in the middle of the ring, Jorge Arce retained his WBClowns “quasi” flyweight title with a sixth-round stoppage of Rosendo Alvarez. Arce said he didn’t want to knock out Alvarez in the first round so he could “punish” him. Arce, 26, and noticeably bigger than the 35-year-old former 105-pound champion, ended it with a left hook to the belly. Alvarez went down, quickly got to one knee, and listened attentively as Referee Vic Drakulich counted to ten….The colorful Arce, who enters the ring sucking on a lollipop (Saturday’s was cherry, inquisitive minds should know), will now move up to 115 pounds, perhaps to face Martin Castillo, one of the slickest boxers around….Bobby Goodman, King’s boxing right-hand man, said there was no truth to rumors that, soon to be turning 67, he was thinking of retirement. He said he was planning to move back to New Jersey, to satisfy his wife’s wishes, but would work out of his home as King’s matchmaker deluxe and would also work all the fights. “I couldn’t leave Don alone,” said Goodman.

King paid about $500,000 to Main Events to take over Judah’s promotional contract, but Kathy Duva said there was a nice bonus, too, when King agreed to let Arturo Gatti, Main Events’ biggest star, challenge Baldomir in July.