David Price has pulled out of his heavyweight fight against Russia's Evgeny Orlov in Germany on 14 December because of a virus.
The bout in Neubrandenburg was set to be the Liverpudlian's return to the ring after two losses to American Tony Thompson earlier this year.
Price, 30, said: "I'm disappointed. I was looking forward to the fight.
"But I wouldn't be doing myself or my fans justice by taking the fight when I am anything less than 100%."
Price has recently signed with German promoters Team Sauerland and also has a new trainer in Adam Booth, who guided David Haye to a world heavyweight title in 2009.
Price was British and Commonwealth champion but relinquished his belts earlier this month after deciding against a fight with domestic rival Dereck Chisora.
Orlov, 35, has a record of 14 wins (10 knockouts), 12 losses and one draw.