Light heavyweight-turned-middleweight fighter Goran Reljic has been forced to pull out of UFC 90 in Chicago on Oct. 25 due to a lower back injury.

Reljic’s management revealed the news to various Internet outlets over the weekend.

The Croat had been slated to fight fellow middleweight Thales Leites in a bout slated to air during the pay-per-view portion of the show but Leites is now left without an opponent.

It is uncertain whether Leites will remain on the card against a new opponent or if he will be taken off the show.

According to his manager, Zoran Saric, Reljic may only be sidelined for two-to-four months. Reljic, who is 8-0, made his UFC debut as a light heavyweight at UFC 84 this past May, where he recorded a second round TKO over American Top Team’s Wilson Gouveia.