Turki Alalshikh, who made the offer, revealed the details to Froch in a recent interview.
"Last year I gave him an offer to fight you and he accepted then the next day he changed his mind. It was not for an exhibition, it was for a real fight. Still, I want to see this fight."
Calzaghe's career spanned from 1993 to 2008. He retired with an unblemished record of 46 wins and no losses. The Welshman held the WBO super-middleweight title from 1997 to 2008, defending it 21 times. He also became the unified super-middleweight champion, holding the WBO, WBA, and WBC belts.
In his final fights, Calzaghe moved up to light heavyweight. He won The Ring light heavyweight title in a split decision against Bernard Hopkins. His last fight was a unanimous decision win over Roy Jones Jr.
Calzaghe's legacy includes notable wins over Jeff Lacy, Mikkel Kessler, Bernard Hopkins, and Roy Jones Jr. Many consider him one of the best super-middleweights in history. He's one of the few boxers to retire without a single defeat.
At the time of the offer, Froch was 46 years old, while Calzaghe was 50 and long retired. The fight remains a fantasy contest that will forever be remembered as one that got away.