The first time a lot of Americans saw Joe Calzaghe was in 2000, on the undercard of the Mike Tyson-Julius Francis card in Manchester, England.

Afterwards, it was hard to understand what all the fuss was about.

Calzaghe, making the fifth defense of his WBO super middleweight title, probed and poked and moved and danced his way to an incredibly boring 12-round decision over someone named David Starie. After that, the crowd and the viewers were seeing stars from the sheer tedium of it all — begging for Tyson, even as old and over-the-hill as he was at the time.

After that, Calzaghe continued to pop up every now and then, and, eventually, you realized that this guy was pretty good. You don’t stop Omar Sheika in five rounds if you don’t have some ability. And you don’t outwork the ultra-tough Charles Brewer if you’re not topflight.

Yes, it’s been obvious for a few years that Joe Calzaghe is the goods. You don’t ever scoff at a 40-0 (31 knockouts) record, 17 title defenses and a reign that has stretches back to 1997.

The problem lately, though, is that Calzaghe is starting to fade.

You could see it in 2003, when Byron Mitchell dropped him in the first round of a wild affair in Cardiff, Wales. Calzaghe came back to stop Mitchell in round two, but he was no longer the elusive ghost that made opponents like Starie swing at air.

And he has struggled at times with his last four opponents, Evans Ashira (W 12), Mario Veit (KO 6), Kaban Salem (W 12) and Mger Mkrtchian (KO 7) — not exactly a memorable lot.

He is 33 now, and slowing down. But a great fighter always has one great fight left in him, even in the twilight of his career. So we should find out if Calzaghe is indeed great Saturday when he meets fellow undefeated champion Jeff Lacy.

* * *

It wasn’t that long ago that Lacy was a good-looking prospect with loads of potential, back when he was beating guys like Ross Thompson (W 12) in 2002 and Richard Grant (W 12) in 2003. You thought, if this guy ever fights as good as he looks, look out.

Well, lately, guess what?

They say that fighters get better with a championship belt wrapped around their waists, and that certainly applies to Lacy, a native of St. Petersburg, Fla.

Starting with his eighth-round knockout of the ordinary Syd Vanderpool for the vacant IBF 168-pound title in 2004, the 28-year-old Lacy, 21-0 (17 KOs), has improved with each fight.

Dramatically.

He had some trouble with the tough Sheika late in ‘04, but still gave the veteran a fierce beating over 12 rounds. Lacy won a unanimous decision. He also may have wobbled for an instant against hard-punching Rubin Williams last year, before registering a hard-earned 7th-round TKO.

Then, against former champ Robin Reid, Lacy began to hit his stride. He issued a brutal beating to the proud Reid, and the fight was called in the eighth. And Scott Pemberton in Lacy’s last fight? Forget about it. He never had a chance. “Left Hook” was simply awesome.

Lacy has been very impressive indeed, quickly becoming one of boxing’s must-see performers. He’s even gotten a taste of the mainstream, appearing in an ad for ESPN radio.

He is strong. He is powerful. And that left hook is a thing of beauty.

But please don’t confuse Joe Calzaghe with Scott Pemberton. Make no mistake, Lacy is in for a fight Saturday night, regardless of Calzaghe’s age.

* * *

This is a classic boxer-puncher matchup. Calzaghe has the fast hands, the quick feet, the all-around skill. Lacy has the brute strength, and the ability to end the fight at any time.

Early on, don’t be surprised if Lacy suddenly looks mortal. Calzaghe knows all the tricks, and his jab is educated enough to bust Lacy up. And when the youngster gets in close, Calzaghe will thwart his efforts by tying him up.

Frustration may even begin to set in for Lacy.

But, as the fight progresses, Calzaghe’s legs will begin to falter as a result of his opponent’s body attack. And then Lacy will start his fight-winning charge.

Behind on points in the 11th round, he’ll uncork one of those giant left hooks, and Calzaghe will hit the deck with a thud. He may even get up, since his heart is as big as Wales.

But then Lacy will apply the finishing touches, and Calzaghe will go home a loser for the first time in his career.

Lacy by 11th round TKO.

Afterwards, the fans in Manchester will know they had seen a good fight. And Calzaghe will go home knowing that, yes, he is a great fighter.