Umar Nurmagomedov has been forced to withdraw from UFC Nashville for undisclosed reasons, and the UFC now seeks a replacement opponent for bantamweight standout Cory Sandhagen.

Multiple people with knowledge of the shift confirmed Nurmagomedov’s withdrawal to MMA Fighting’s Mike Heck after an initial report from TheSchmozone. UFC Nashville takes place Aug. 5 at Bridgestone Arena and airs on ESPN and ESPN+.

Nurmagomedov, a younger cousin of former lightweight champ Khabib Nurmagomedov, hoped to extend his unbeaten streak to 17 fights and climb into title contention at 135 pounds. The 27-year-old fighter has won four straight since signing with the UFC, most recently stopping Raoni Barcelos at UFC Vegas 67.

Sandhagen, meanwhile, aims to gain momentum for another shot at the title after high-profile setbacks against now-champion Aljamain Sterling and ex-champ T.J. Dillashaw. The 31-year-old Colorado native has won his past two fights, most recently outpointing Marlon Vera at UFC San Antonio.

Here is the current card for UFC Nashville: