Joe Calzaghe's shot at Glengoffe Johnson's IBF light heavyweight title will be on 5 June in Manchester.
"Joe is definitely fighting, and I fully expect him to become a two-weight champion," said the 32-year-old's promoter Frank Warren.
The fight will be Calzaghe's first at the weight, having held the WBO super middleweight title for seven years.
Ricky Hatton will also feature at the MEN Arena in a card to appeal to US TV network Showtime.
Hatton is being lined up for a shot at IBF interim light welterweight holder Sharmba Mitchell.
Glen Johnson claimed the vacant IBF light heavyweight title in February with a victory over Clinton Woods in Sheffield.
"Joe is talking a lot of talk, let's see if he can walk the way he talks," said Johnson.
Calzaghe will not vacate his super middleweight title when he steps up to face Johnson.