From Wikipedia
In the first round, Calzaghe, who was seven years younger than Hopkins, was knocked with a straight right hand which led to Calzaghe suffered a small cut on the bridge of his nose.
Calzaghe was warned by referee Joe Cortez in the second round for throwing a low blow. Cortez later warned both fighters for hitting behind the head. The fight was definitely slipping into the pattern that favored Hopkins - slow, down and dirty.
Cortez called a timeout and brought both fighters to the center of the ring for a lecture in the fourth round. He did that after both of them had committed fouls - Calzaghe for holding and hitting and Hopkins for hitting on the break. Calzaghe still managed to land a couple of blows to the back of Hopkins' head at the end of the fifth round.
Calzaghe never got the opportunity to showcase his blazingly fast hands and his combinations. Hopkins would smother him whenever he tried to come in and throw more than one punch. But Hopkins seemed to slow down in the later rounds.
In the 10th round, Calzaghe hit Hopkins with a punch that was low. Hopkins crumpled to the canvas and was slow getting up. Cortez didn't take away a point, but gave Hopkins a two-minute break to gather himself. Calzaghe thought Hopkins was acting and waved for the crowd to show their displeasure with Hopkins. The fans booed on cue.
"It was a low blow," Hopkins said. "It knocked my privates out of the cup. That's why Joe gave me (two) minutes."
Hopkins complained of another low blow in the 11th round, but this time Cortez ignored his plea for time and told him to keep fighting. He came out and tried to ferociously attack Calzaghe, but Calzaghe charged back.
'Round 12: "The undefeated record is on the line and Calzaghe comes forward like he knows it. But Hopkins ties him up time and again. A frustrating final round for the Welshman and a frustrating fight really. Some experts disagree with me but I think Hopkins has this. Like I said before, I hope I'm wrong." ' -BBC Live Text Commentary.
'Round 12: "A round that started with Calzaghe's corner imploring their man for a knockout ends with a strong flurry from the Welshman, but will it be enough? It's close, but Calzaghe was put down in the first round and Hopkins never allowed him to get near enough to show his talents to their best advantage. For me, it's Hopkins' fight, with the best that Calzaghe can hope for a split decision." ' -The Guardian Live Text Commentary.
In the end, judges Chuck Giampa (116-111) and Ted Gimza (115-112) scored the fight for Calzaghe, while judge Adalaide Byrd (114-113) scored the fight for Hopkins. According to CompuBox, Calzaghe landed more punches on Hopkins than any of his previous opponents.
The Associated Press, New York Daily News, Yahoo! Sports, ESPN.com and Fighthype all scored it 114-113 for Bernard Hopkins.
"It was a good fight. I thought Bernard (Hopkins) won though," commented former undisputed Heavyweight champion, Mike Tyson.
"Hopkins beat Calzaghe, let's not forget. It was a split decision and a very close call, Calzaghe got beat up, his nose was bust and Hopkins was unmarked." Super middleweight champion Carl Froch commented, "Come on, put it in perspective and let's not lose our minds here, he was put on his ass by a 43-year-old (Bernard Hopkins) and 40-year-old (Roy Jones Jr.) in his last two fights."
Carl Froch