Calzaghe's pummeling of Jones offers a round of lessons

As Joe Calzaghe celebrates his legacy-defining victory over Roy Jones, Jr, here's a look at five things we learned from Saturday night's card at Madison Square Garden

1. For Calzaghe, 175 pounds is a perfect fit.

After making 21 successful defenses of his super middleweight title between 1997 and 2007, the undefeated Welshman reached a crossroads. He'd run out of viable opponents at 168 pounds and, at 36 years old, it was becoming more and more of a strain to make weight.

So Calzaghe moved up to light heavyweight for his U.S. debut against Bernard Hopkins in April, overcoming a knockdown in the first round for a cagey and hard-fought unanimous decision victory. He looked even more impressive in his second outing at 175 pounds against Jones, rallying again from a first-round knockdown -- "It was déjà vu, man!" -- to capture 11 straight rounds and a lopsided decision victory.

Calzaghe has strongly hinted at retirement, perhaps tantalized by the legacy of becoming the second fighter in history to walk away undefeated and undrawn after 40 or more bouts. He's never been motivated by money. But as a competitor, it's hard to imagine Calzaghe retiring after looking so sharp through 24 rounds at the unconquered frontier of 175 pounds. He hasn't sacrificed any of the hand speed or elusiveness with the extra weight and his conditioning remains supreme.

But who would he fight?

There's a rematch with Hopkins, who watched Saturday's fight from ringside and would reportedly consent to a fight in Wales. But the most attractive pairing from a fan's perspective would be Chad Dawson, the undefeated IBF light heavyweight champion. In fact, the 26-year-old southpaw issued a press release just one hour after Saturday's fight -- at 1:25 a.m. on Sunday morning -- congratulating Calzaghe on his victory and offering up a unification fight in the U.K.

When a reporter passed along the information during the post-fight presser, Calzaghe allowed a wry grin.

"I just stepped out of the ring about 15 minutes ago, man. Let me enjoy this fight before I think about fighting somebody else," said Calzaghe. "What do you think I am, a sadist?"

2. Roy Jones, Jr. is finished. (Sort of.)