UFC bantamweight champion Sean O'Malley has publicly criticized former two-division champion Conor McGregor, calling him a 'drug addict' in need of rehab after McGregor mocked O'Malley's past suspensions for Ostarine. The tension reignited after McGregor shared a now-deleted post ridiculing O'Malley's claim that Ostarine contamination could occur through sweat transfer. O'Malley responded by pointing out McGregor's poor recent fight record and questioned his skills, although he acknowledged McGregor's entertainment value and left-hand prowess. This feud follows a similar exchange in May 2024 related to boxer Ryan Garcia's positive tests for Ostarine. Despite the harsh words, O'Malley mentioned he remains a fan of McGregor.