LAS VEGAS, March 30 – Let’s leave it to the theologians to discuss why, from God and Jesus to Abraham and Isaac, the bible is full of stories about fathers’ willingness to sacrifice their sons. In boxing, it probably is best left to the shrinks to figure out the patriarchs. All I know is that Jack Mesi must have some inner qualms when he leads his son Joe to the ring Saturday in Puerto Rico. It is my belief that this is a case of a father supporting his son’s calculated risk to live out his dream. Wish them well and, meanwhile, contemplate a fistic patriarch who may have sacrificed his own career for his son.

Papa Byrd wouldn’t have it any other way. Joe Byrd Sr. will leave in a couple of weeks with his son Chris for Mannheim, Germany, and their April 22 return match with Wladimir Klitschko. That Chris Byrd, the longest reigning of the four alphabet heavyweight champions, is even in this position is a remarkable testament to Papa Joe’s ability.

“He took a non-punching middleweight to the heavyweight title,” said Chris.

But in a business where success usually breeds imitation, Papa Byrd does not have a gym full of stars. Maybe it was being out of the way in Flint, Mich. Maybe in Brockton, Mass., Goody Petronelli has waited and waited for another Marvelous Marvin Hagler to walk into his gym, but Joe Byrd is content to be training elementary school kids back in Flint. He left maybe 15 kids, including a few seniors (there’s a heavyweight named Jovin Carr he said who just turned 18 and he advised remembering the name, though he wasn’t sure how to spell it) back in Flint, under the care of Momma Byrd. His wife, Rose, was the only trainer Joe Byrd says he ever had back when he was fighting. She will join her husband and son at the U.S. Army base near Mannheim a few days before the fight and, as usual, work the corner.

You’d think this Momma and Papa operation would have expanded by now. Papa Byrd was not exactly unknown in the business before the youngest of his eight children went on to heavyweight fame. He was the head coach of the 1992 Olympic team that, hindered by the new computerized scoring rules, was held to one gold medal – Oscar De La Hoya’s – but which produced six future world champions, including Chris.

He’s had a couple of guys pass through. For a while, he was Paul Vaden’s trainer. And Tim Littles’. He actually worked with Floyd Mayweather Sr. for a year (“He got shot or stabbed, I think, but he was one of the best ‘til his son came around”).

“I could’ve built a stable of pros, but I have a family of eight,” Byrd Sr. said. “I was making good money at GM, and I had my own team.”

And he had the little kids in the basement of a Flint elementary school, where he began his training career, teaching discipline more than double-hooks. Chris, who has moved here with his family, has asked his father to move out to the desert, but there are still five-year-old kids back in Flint and Papa Joe is not about to fly the coop.

He said there were a lot of trainers who took over fighters from other coaches – he still uses the amateur term – but he liked guys who took kids from the juniors “all the way to world championships, like Emanuel Steward did. That’s what you call a trainer.”

Even at the start, he said he had this crazy dream of becoming Olympic coach and having one of his kids on the team. “I didn’t see no way,” he said, but it happened.”

The kid he felt most likely to succeed was Ryan, who was a terrific flyweight – Steve McCrory, the 1984 Olympic champion, could never beat him. Was he better than Chris? “Oh, my God, yes,” said the proud Papa. “But he had a car accident. A truck ran into his car and he was thrown out and two other cars hit him. He was lucky to live, but it was the end of boxing.”

Chris started boxing at the age of five, but seemed more interested in playing basketball – the game where his two sisters earned college scholarships. “But when he was about 14 or 15, he started to see his brothers win trophies and medals from boxing and decided he could do that, too.”

Papa Byrd was still fighting himself. In-between shifts at the General Motors plant where he spent 34 years, mostly in building management, he was a pro for 12 years. Said he was actually the last man to be in a ring with Sugar Ray Robinson. Byrd said it was an exhibition in Trenton, back in 1973, about eight years after Robinson had finally retired at the age of 44. And how was Robinson back then?

“Sweet,” said Byrd.

Chris, who won an Olympic silver medal as a 6-foot-1 middleweight with long arms, is the physical opposite of his father. Papa Byrd is more like a squat owl. “I was short and I had power,” he said. He fought light-heavyweight and heavyweight, thinks his record was “16 or 17 and 12.” The son of Mississippi sharecroppers, who moved at the age of 13 to stay with a sister, is 5-foot-7, “and a half,” and he once fought Earnie Shavers and lasted until the third round when he blew his nose after getting hit by one of those sledgehammers and his eye swelled up. He fought Ron Stander, who was one of Smokin’ Joe Frazier’s title challengers, the one whose wife said “You don’t enter a Volkswagen in the Indianapolis 500 unless you know a hell of a shortcut.”

“They said I was quick as a flashbulb and a wise old pro,” said Byrd. “He got the decision, but the judges were sleeping.”

He’s seen it all. The computer scoring that jobbed his Olympic flyweight, Eric Griffin, and took the air out of the 1992 U.S. team. Chris got silver and Tim Austin bronze, but there was only Oscar’s gold. Yet the six world champions – Chris Byrd, De La Hoya, Austin, Vernon Forrest, Raul Marquez and Montell Griffin – attested to the quality of the squad.

So there he was yesterday, working with his one-star stable of pro fighters, at the UFC Gym here. That’s Ultra Fighting Championships, the game that took Marc Ratner away from the Nevada State Athletic Commission (to be replaced by assistant state District Attorney Keith Kizer, which will be announced tomorrow). It’s clean and quiet and every now and then Papa Byrd would check to make sure Chris wasn’t overdoing it on his so-called “light” day between sparring sessions.

“The real Chris is back, he’s so happy,” said Joe Byrd.

Byrd was dreadful in his last defense, against DaVarryl Williamson. The feuding with Don King was getting to the IBF titleholder. The wise old owl stayed out of those arguments. But now, he said, he could see the difference.

For the Williamson fight, a magnificently dull decision won by Byrd last year, “I was here, but he wasn’t here, the Chris I know wasn’t here.

“This fight,” he said, “is different.”

Of course, this time Byrd is having to travel to Germany again to face Wladimir Klitschko, who beat him very one-sidedly in 2000. Chris’s eyes were swelling shut by the third round; Papa still thinks there was some hanky-panky going on.

“They played a lot of games with us,” he said. “We came over there (Cologne) with the world champion and they put us in a hotel where I wouldn’t put my amateurs. We had to eat at a whistlestop – what I call fast food. Then they told us fight night we’d be on at 9:30 and at 10:30, after warming up and cooling down a few times, we were still in our dressing room.

“I was going to stop it, especially in the 11th round, I was walking up the steps, but Patrick (another son) pulled me back and said Chris had to go the distance.”

Chris Byrd said that it was “the worst night of my whole life – not just my career, my whole life.”

This time, though they will be in an 18-foot ring in Mannheim, Byrd is not looking to go the distance. He is looking to win. He’ll be 36 in August and there are no more big paydays if he loses. And his father will be 70 on May 10 and Chris knows what Papa wants for that birthday.

PENTHOUSE: To Gerald Eskenazi, one of my many linear successors on the New York Times boxing beat, congratulations for being named to the City College of New York journalism hall of fame. Esky, one of the nicest guys in the world (he thought Al Braverman was a prince), tapped me on the shoulder at the Oliver McCall-Larry Holmes fight at Caesars Palace and pointed out, that sitting side by side by side, were Vic Ziegel, yours truly and himself – three CCNY buchas in the front row of the press section at a major Caesars Palace boxing card (Julio Cesar Chavez, Felix Trinidad Jr. and Terry Norris were also on it with the Bruce Seldon-Tony Tucker WBA heavyweight title bout). Who’d have thought CCNY would produce boxing writers. Well, I’m a bit ashamed to admit that Nat Fleischer also went there.

OUTHOUSE: Zab Judah, for brushing off the press again on a conference call the other day. Hey, it wasn’t our fault you lost to Carlos Baldomir (or “Baltimore,” as your increasingly loudmouthed father called him at the same time saying Floyd Mayweather Jr. was a “big mouth”) and cost yourself millions of dollars. Be glad you’re getting a chance to still face Mayweather next weekend. The party line from Yoel Judah and promoter Don King is that Zab was too “focused” on the fight to be bothered by media types. I am hearing that Floyd, too, is focused – “he just doesn’t want to win, he’s way beyond that now,” said Mayweather adviser John Hornewer.

APRIL FOOL: Both Byrds, Papa Joe and cousin Chris, think Lamon Brewster (one grandmother was named Byrd, which makes him a cousin of his title-holding peer) should get by Sergei Liahkovich on Showtime’s freebie Saturday from Cleveland (to start after the Final Four, root for no overtimes).” Brewster will get to him,” said Joe Byrd. Chris said, “Lamon is at the top of his game now and he’s still really hungry to prove he belongs. His confidence has never been so high.” He said Liahkovich was a “good fighter, but inactivity has to hurt.” He said the Belarusian fighter was originally signed by King “to be my opponent, but Don’s got so many guys he can’t keep them all busy.”…Chris Byrd thought his buddy Hasim Rahman won “fairly easy” against James Toney “and he could’ve made it a lot easier if he had stepped back.”

KILROY IS HERE: Was going to put Marc Ratner in the PENTHOUSE again, but he probably deserved a permanent abode. Am glad he’s going to make a lot more money at the UFC. He’s 61, probably had no more than three or four more years left at the Nevada commission, so the move makes a lot of sense for his family’s sake. Of course, as Gene Kilroy, the Great Facilitator says, “he leaves awfully big shoes to fill.” I’m not sure what size foot Keith Kizer has; he was recommended by the outgoing Ratner to take over as the executive director and my buddies here tell me he’s a good man. But his only experience with the fighters themselves seems to be when the commission was meting out discipline (Mike Tyson, Fernando Vargas). Kilroy himself might have been a better choice. Think of it. The man was with Muhammad Ali for 12 years and knows everyone. He’s been living in Vegas for 27 years and there’s probably not a casino owner who hasn’t or will hire him. He’s friendly with fighters from Tyson to the Klitschko brothers. He’s one of the true straight-shooters in a mostly b.s. sport. Kilroy, who still thinks Ratner should be named the Federal commissioner, would have been a brilliant choice, if he would have accepted.

MORE DISS AND THAT: Please, is Don King becoming the first black owner of a diaper company the greatest straight line in boxing history?…Maybe some website should have a contest to come up with the best example. The prize could be pre-owned diaper samples. The fact that Ricky Hatton and Floyd Jr. have both given up their junior welterweight titles says less about weight problems than about the value of so-called championships. Hatton will make his U.S. debut against Luis Collazo, who has a WBA welterweight trinket, but it is not an easy assignment, says John Hornewer. “Collazo reminds me of Hector Camacho, after he fought Edwin Rosario,” said Horny. “He is very hard to find and he can box.”…Am not completely sold on Edison Miranda as the next big middleweight star. Yes, knocking out Howard Eastman was impressive, but the way his legs turned to spaghetti when he got nailed by the aging Brit was not conducive to great confidence.Glad to see John Jackson of Forum Promotions is back and going to kick some butt. Jackson recently underwent partial amputation of his left leg because of diabetes, but signaled his return to action by signing the Marquez brothers – Rafael and Juan Manuel – to a three-year deal. No way Jackson would have allowed Juan Manuel to go to Indonesia for $30,000 or so….If Arthur Abraham is this big, bad dude everyone says, then why is he fighting Raymond Joval?…Another candidate for the PENTHOUSE is Joe Mesi, for sticking his neck out for his dream. If he were my brother, I’d beat him up (with body shots, of course) to stop him from risking more subdural hematomas. But I applaud his guts and hope his doctors are right that he’s at no more risk than any other fighter. Guys like Mesi are why people are attracted to this brutal business in the first place.

(Happy birthday, darling Marilyn.)