Mirko Cro Cop has suffered an undisclosed injury that has forced him out of Bellator 200 this weekend.

The former UFC and PRIDE fighter was expected to face Roy Nelson in the main event this Friday in London but now the Croatian heavyweight has been forced to withdraw with just days remaining until the show.

While a replacement is being sought for Nelson, Bellator has already moved the middleweight title fight between Gegard Mousasi and Rafael Carvalho into the headline spot on Friday’s card. The welterweight fight between Michael ‘Venom’ Page and David Rickels will now serve as the co-main event.

Bellator officials confirmed the news on Monday following an initial report from the Telegraph in the U.K.

It’s a devastating blow to Bellator 200 as Cro Cop was making his promotional debut for the company in a fight that was supposed to serve as an alternate bout for the ongoing heavyweight grand prix tournament.

It’s unknown at this time if Bellator will be able to secure a last second replacement so Nelson can still compete on the card.