Oleksandr Usyk will defend his unified world heavyweight title against Daniel Dubois in Poland on August 26.
The fight will take place at the 24,000-capacity Tarczynski Arena in Wroclaw.
WBA mandatory challenger Dubois last fought in December, recovering from a leg injury to defeat Kevin Lerena by way of knockout.
Pound for pound star Usyk is the IBF, IBO, WBO and WBA champion having defended his titles against Anthony Joshua last year.
The 36-year-old had been expected to fight Tyson Fury to determine the first undisputed world heavyweight champion since Lennox Lewis in 2000.
Talks, however, fell through and reports now suggest Fury will instead meet former UFC star Francis Ngannou in an exhibition bout.
While boxing has enjoyed a year full of big fights in other divisions, the heavyweight scene has hit a gridlock.
Still, Joshua is widely expected to face Deontay Wilder in Saudi Arabia this winter amid reports suggesting a rematch with old rival Dillian Whyte is edging closer.
