One of the world's most famous mixed martial artists may not be participating at the sport's marquee event.
Conor McGregor, the reigning Ultimate Fighting Championship (UFC) featherweight champion, has been pulled from the UFC 200 event due to be held in July, the promotion revealed on Tuesday.
According to an article posted on the UFC website, the "decision was made by the promotion after McGregor informed UFC officials that he would not participate in any promotional activities, including a commercial shoot and press conferences."
The UFC said it was working on a new main event.
McGregor, known as much for his braggadocio as his ability to deliver devastating knockouts, was scheduled to fight Nate Diaz in a rematch at UFC 200 in Las Vegas. Diaz had beaten McGregor in a welterweight bout at UFC 196 in March.
For his part, the 27-year old Irishman sent out a cryptic tweet suggesting he had quit the sport.
Whether McGregor is genuinely quitting or this is just a tactic to get better terms is less certain. In the past, fighters such as Randy Couture and B.J. Penn have returned to the promotion having announced their retirement, while the promotion has also buried differences with fighters before.