Britain's Dereck Chisora will face Vitali Klitschko on 18 February after beating David Haye to a fight with the WBC heavyweight champion.
Chisora, 27, will take on the Ukrainian in Munich, Germany.
He has twice been scheduled to face Klitschko's brother Wladimir, who pulled out both times through injury.
Chisora said: "Wladimir Klitschko did not fight me but now I'm going to get the championship belt by beating his older brother."
Chisora lost a split decision to Robert Helenius in a European title challenge on 3 December in his last fight, but is confident about his February title tilt.
He said: "I'm going to show Vitali Klitschko that his time has expired and send him into retirement.
"When his younger brother then wants a fight against me I'll be ready to bring all the championship belts to London."
But Chisora will start as a heavy underdog against Klitschko at the Olympic Hall, having lost two of his last three contests.
In July, a poor performance saw him lose his British and Commonwealth titles to Tyson Fury and, after a routine win over Remigijus Ziausys, he was defeated by Helenius last time out.
Vitali Klitschko was impressed with Chisora's performance against Finland's Helenius though.
He said: "Chisora showed in his last fight, which he lost unfairly, that when his opponents are much bigger he can fight well on the inside.
"I will take warning from his excellent performance against Helenius and train intensely and meticulously as always. I won't let all his talking affect me, however."
The news of the fight leaves Haye in an uncertain position, with the former world champion officially retired but still keen to face Vitali after losing to his younger brother.