Officials confirmed Miocic's withdrawal from the UFC Fight Pass card on Tuesday. MMAJunkie.com first reported the injury. The UFC is exploring late-replacement options for Rothwell (35-9) to potentially remain on the event, which takes place at 3Arena.
Miocic (13-2) has fought just once in 2015. He earned a fifth-round TKO finish against veteran Mark Hunt on May 10. The 33-year-old is 4-1 in his last five fights, with the only loss coming via narrow unanimous decision against former champion Junior dos Santos.
Rothwell is looking to add to a three-fight win streak. He is coming off a first-round submission win against Matt Mitrione at a UFC Fight Night on June 6.
ESPN.com ranks Miocic and Rothwell the Nos. 4 and 6 heavyweights in the world.