LAS VEGAS (AP) — UFC bantamweight champion Amanda Nunes says sinusitis is the reason she dropped out of her title defense at UFC 213 with just a few hours’ notice.

Nunes revealed her condition in postings Sunday on Twitter and Instagram.

Nunes says she felt out of breath during her weight cut and “felt off balance from the pressure in my sinuses. I was not feeling well enough to risk getting punched in the head with such pressure.”

UFC President Dana White and opponent Valentina Shevchenko criticized Nunes on Saturday for her decision, which forced the promotion to scrap the main event of its pay-per-view show. White says he won’t book Nunes as a main event in the future.

Nunes’ fight with Shevchenko could be rescheduled for UFC 215 in Edmonton in September.