TJ Dillashaw is out of his clash with Renan Barao at UFC 186.
The Bantamweight champion suffered broken a rib in training and isn't clear to compete in time.
It marks the third straight time the title fight has had to be changed since Dillashaw won the title.
A cursed run thus far
At UFC 173, the underdog Dillashaw overcame the odds to beat Barao for the UFC's Bantamweight title.
Yet since then, injuries have blighted the division and the title has only been defended once but that was a fight taken on 24 hours notice.
That was the first time the fight was changed and it was due to Barao passing out from dehydration on the day if weigh-ins.
Joe Soto stepped up from the prelims to the main event in his UFC debut and was soundly beaten by the superior Dillashaw.
Then Dillashaw was scheduled to face former champ Dominick Cruz but he too fell to injury, tearing his ACL in training.
Barao had been pushed into the title fight as a replacement but the injury bug strikes again and the UFC have to delay one of the biggest fights of the year.
In their place, Demetrious Johnson will defend his Flyweight title against Kyoji Horiguchi, but for many it's a clear downgrade.
Could this be one of the first bombs of the year for the UFC?
Despite being one of the best pound for pound fighters in the world, Johnson hasn't seen many PPV buys when he tops the card.
One of the main concerns for the UFC in recent years has been the lack of star power and falling buy rates.
So with the previous buy rates for Johnson bouts being estimated at some of the lowest in UFC history, their hand has been forced.
This year has been a successful but tumultuous one so far for the organisation, and without Ronda Rousey, they'd be facing their second failure of the year.
UFC 184 was carried by Rousey's defence of her title but the enthusiasm for the card was low, especially after Chris Weidman-Vitor Belfort was scrapped.