An injury has forced heavyweight champion Guram Gugenishvili (11-0) out of next week's M-1 Challenge 27 headliner.
In his place steps Maxim Grishin (9-5), who now meets Kenny Garner (7-3) for an interim title.
M-1 Challenge 27 takes place Oct. 14 at Grand Canyon University Arena in Phoenix, and the main card airs on Showtime.
According to M-1 officials, Gugenishvili, who was wrapping up his camp at Xtreme Couture in Las Vegas, suffered an elbow injury during a Wednesday training session. After meeting with a physician, he wasn't cleared to fight and is expected to be sidelined four to six weeks.
"This is tremendously unfortunate as it is now the second time this has happened," M-1 Global Director of Operations Evgeni Kogan stated. "No one is more disappointed about the change in circumstances than Guram himself. He was absolutely gutted when breaking the news to us. We hope Guram makes a swift recovery so he can return to action as soon as possible."
Garner was supposed to rematch Gugenishvili, who earned a submission win a year ago in their first meeting. Since the loss, Garner has picked up a pair of knockout victories (and owns five KOs in his seven career victories).
Grishin, who is one of Fedor Emelianenko's training partners at Red Devil Sport Club, is a three-year M-1 vet. He's won five of his past six fights (all via stoppage), and the lone defeat came to Gugenishvili.
In addition to the main-event change, officials announced a pair of fights for the preliminary card. They include lightweights David Morgan vs. Silvester Villereal and welterweights Mike Chavez vs. Joe Martinez.