Alexander Gustafsson will not compete at UFC Fight Night 100 on November 19 after suffering a recurrence of a chronic back injury.
Gustafsson was supposed to face Antonio Rogerio Nogueira in the main event in Sao Paulo, Brazil, but due to his injury, he has been replaced by Ryan Bader.
Bader has faced Nogueira in the past, beating the Brazilian via unanimous decision at UFC 119 in September 2010.
Bader will head into the fight on the back of a second-round knockout win over Ilir Latifi at UFC Fight Night 93 last month. With his victory over Latifi, Bader has now won six of his last seven fights.
Nogueira, meanwhile, also triumphed in his last fight as he beat Patrick Cummins via TKO in the first round at UFC 198 in May. The 40-year-old has emerged victorious in three of his last five bouts.
Gustafsson, who is currently the No.2-ranked UFC Light Heavyweight contender, will be disappointed to miss out on his fight with Nogueira as he won his last fight against Jan Blachowicz via unanimous decision at UFC Fight Night 93.