Enzo Maccarinelli will be aiming for his second European crown when the former cruiserweight world champion fights Dmytro Kucher in London in June.
Frank Warren will promote Maccarinelli's shot for the vacant European belt against the Ukrainian at Bethnal Green's York Hall on 10 June.
The 35-year-old, former WBO champion, won two European title fights in 2010.
Maccarinelli, replaces the Derby-based Jamaican Ovill McKenzie who withdrew through injury.
The Bonymaen-boxer is unbeaten in three and beat American great Roy Jones Jr in his previous fight in Moscow in December.
He switched to the light heavyweight code for a world title opportunity in 2014 against Juergen Braehmer, but has now been told by his trainer Gary Lockett to stick to the cruiserweight division.
Maccarinelli originally expected to be a pundit for the show in June.
"I had a phone call from BoxNation asking if I'd cover the fight as a pundit," he explained.
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An hour later I had a phone call from my trainer Gary Lockett asking if I fancied stepping in to fight Kucher; it was a bit mad!
"Obviously I'm always in the gym so I jumped at the chance.
"I've won it before so it'll be nice to become a two-time European Champion.
"More importantly it gets me one step closer to another world title which is my ultimate goal.
"I'm taking things one fight at a time and hopefully I'll get another shot at the biggest prize.
"First of all I need to take out Kucher on June 10 and I intend on doing it in style."