Callum Smith is preparing to take on seven-time world champion kickboxer Nieky Holzken in the World Boxing Super Series semifinal on Saturday after the withdrawal of original opponent Juergen Braehmer.
With WBA Super champion George Groves awaiting in the final of the super-middleweight tournament, Smith (23-0, 17 KOs) had been due to meet veteran German Braehmer (49-3, 35 KOs) in Nuremberg.
Following German media reports that Braehmer is unable to fight due to an infection, his place went to unbeaten Dutchman Holzken (13-0, 10 KOs), who had been scheduled to face Dmitrii Chudinov on the undercard.
In a press statement on the World Boxing Super Series website, Braehmer said: "Unfortunately, a fight in this state is out of the question. It is not possible for me to go into the ring like this and I would like to apologise to my fans. I was well prepared and looking forward to fighting Callum."
The 34-year-old Holzken was a late-comer to professional boxing and only turned professional in 2013 but scored an impressive second-round knockout of Viktor Polyakov in early February.
'The Natural' Holzken said: "I signed up as a substitute fighter so I'm in great shape and prepared for Saturday. I've watched Callum fight many times. I study everyone in my weight division. He's a good, solid fighter. We're both big body punchers. It will make for an excellent fight.
"Callum, you better be ready, because I am, and I'm coming to beat you!"