Maryland, April 6: Oleksandr Usyk's heavyweight debut against Carlos Takam has been confirmed for May 25 in Maryland.
The Ukrainian had stated his intention to step up to the heavyweight division having cleaned up at cruiserweight.
A bout against Takam had been mooted, although the fight was reportedly set for May 18 in Chicago.
Usyk (16-0) and Takam (36-5-1) will instead face off the following week at the MGM National Harbor in Oxon Hill.
"May 25 marks a major moment in my career when I move to the heavyweight division," said Usyk.
"At cruiserweight, I did it all and became the undisputed champion and that is my goal now in the heavyweights. This is the ultimate challenge and it begins on May 25 against Carlos Takam.
"It's a tough first fight but I need to test myself against world-class opposition on my new road to undisputed."
Welcome to the land of giants! Undisputed P4P king @usykaa will make his heavyweight debut against @carlos_takam May 25 @MGMNatlHarbor live on @DAZN_USA in the USA and @SkySportsBoxing in the UK Here we go!! Tickets on pre sale on Wednesday - General sale on Thursday! pic.twitter.com/jQBKlKxshz— Eddie Hearn (@EddieHearn) April 5, 2019
Takam added: "Usyk has achieved everything in the cruiserweight division – I am ready to welcome him to the new world of heavyweight boxing.
"I can promise that this will be a great fight and I will provide Usyk with a huge test on his heavyweight debut. I have huge ambitions of my own in the division and this fight will provide me with the chance to prove that."
Promoter Eddie Hearn, who has suggested he expects Usyk to face Anthony Joshua next year, said: "The time has come for the ultimate challenge for Oleksandr Usyk.
"This pound-for-pound star had dominated the cruiserweight division, becoming undisputed champion after just 15 fights.
"Now he takes the daring leap to the land of the giants as he attempts to repeat his achievements in the heavyweight division."
Usyk became the undisputed cruiserweight champion when he defeated Murat Gassiev in Moscow in July last year, before defending his titles against Tony Bellew in Manchester in November.