youth, yesterday vs. tomorrow.

More often than not, the handlers of the kid on the way up accept such bouts only if they're convinced the old champ with residual name value is bobsledding the downhill side of his career mountain. But surprises can and do happen; sometimes the faded veteran is able to reach back in time to find some vestige of his former glory.

How will Friday night's pairing of 41-year-old ex-WBA heavyweight champion Bruce Seldon (38-6, 34 KOs) and world-rated Kevin Johnson (19-0-1, 6 KOs) at Bally's Atlantic City play out? Depends on whom you ask.

"I'm pretty sure of what Joe DeGuardia [Johnson's promoter] was thinking when he took this fight," said Jim Kurtz, Seldon's longtime manager. "He thinks Bruce is 41 going on 50, and fat. But I really believe Joe underestimated him. In reality, Bruce is more like 41 going on 30, and he's in fantastic shape."

DeGuardia, whose company, Star Boxing, promotes the 28-year-old Johnson, calls Seldon a "potentially dangerous" opponent, but one his guy should handle no matter which description is closer to the truth.

"I think in Kevin I have the next heavyweight champion of the world," DeGuardia said with the zeal of a real-estate agent or car salesman working on commission. "He's extremely talented, he's fast and he has the best jab in the business. He talks like [Muhammad] Ali and jabs like [Larry] Holmes. He has speed and reflexes. And he's charismatic, which is exactly what the heavyweight division needs."

From what I've seen of Johnson, DeGuardia is probably overstating the quality of his product. Maybe Johnson isn't Spam, but he's not filet mignon, either. Born in Asbury Park, N.J., and now a resident of Atlanta, the 6-3 "Kingpin" lacks power, and that's the primary asset for any wannabe heavyweight star, no matter how chatty and personable he might be.

But if Johnson can approach the success achieved by the vintage, mid-1990s Seldon, he'd be an upgrade over what passes for heavyweight contenders in these bleak times. To be sure, Seldon was never a superstar, even though he briefly held a version of a world title, but at his best he was an entertaining fighter with a bodybuilder's physique, a jolting jab and enough pop to usually seal the deal whenever he got his man in trouble.

Alas, the flip side of Seldon was far less appealing. His jaw was chandelier-fragile, he had a stamina problem that made him increasingly vulnerable in the later rounds of bouts, and his confidence was often shakier than a young tree in high winds. When he relinquished his WBA title to Mike Tyson, on a first-round technical knockout on Sept. 7, 1996, he went down from a punch that barely grazed the top of his head. The consensus at that time was that Seldon, whose nickname is the "Atlantic City Express," was victimized more by his own anxiety than by Tyson's destructive fists.

Derided as a fraud and a quitter, Seldon disappeared from public view and didn't fight again for 7 1/2 years. When he did return to the ring, his comeback was ignored in large part because his physique-by-Hercules had so noticeably softened. The same guy who was a veritable Adonis at 230 or so pounds weighed in at 251 in being stopped in nine rounds by Gerald Nobles, and was a career-high 263 when he fell in two rounds to Tye Fields.

That's when Kurtz sat down Seldon for a heart-to-heart.

"We talked about a lot of things," Kurtz said. "I said, 'Bruce, if you really want to continue with this, you have to get your weight down and totally dedicate yourself to boxing again. If you can't, there really isn't any point in going on.' ''

The message apparently registered. Seldon came in at 235, 230 and 225 pounds, respectively, for his three most recent fights, all knockout victories, albeit against third-tier opponents. For his fifth-round stoppage of Livin Castillo on May 31, he was the lightest he'd been since he weighed in a 224 1/4 for a unanimous decision over Mike Dixon on July 9, 1992.

Of course, having six-pack abs at 41 doesn't necessarily mean a fighter can travel back in time to his mid-20s' prime. Reflexes slow, and Seldon will be duking it out with Father Time on Friday just as much as he will with Kevin Johnson.

But Kurtz views the scorched-earth heavyweight landscape and believes there has to be as much opportunity for Seldon as for Johnson to advance with a victory. We are living in an increasingly Green world, so why not recycle boxing's big men as we do aluminum cans?

"Oliver McCall and Ray Mercer are still around, too," Kurtz said, mentioning a couple more fortysomething heavyweights. "They know what Bruce knows: One good win is all it takes to get right back in the mix again.

"To land a fight with someone like Kevin Johnson, who is considered one of the up-and-coming heavyweights, is all Bruce has been asking for. It gives us all a chance to find out where he is at this point."

Bop 'til you drop

The fact that each man is coming off the only loss of his career - Diaz to Nate Campbell, Katsidis to Joel Casamayor - likely will put even more pressure on them to ratchet up their alreadyhigh excitement quotient. *

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