UFC 189 was an event that had the UFC embark on an unprecedented world tour to promote. It is one of the most highly anticipated fights in the history of the sport. UFC president Dana White has said it could reach a record one million PPV buys. And now, it might not happen as scheduled as UFC Featherweight champion Jose Aldo has reportedly suffered a fractured rib during training.

A report from Brazilian outlet Combate says that Aldo suffered the injury during a sparring session after a teammate landed a kick to the champion's midsection. Aldo reportedly fell down immediately after the hit and was taken to the hospital for examination where CT scans confirmed a fractured rib.

Guilherme Cruz of MMAFighting.com, says that with the injury, Aldo could "potentially require three to four weeks of treatment." Aldo's camp has not yet decided on whether or not to pull out of UFC 189, and is reportedly discussing options with his team and his doctors on how to continue to fight.

White took to Twitter to calm fans down after word of the injury quickly spread succinctly tweeting, "Relax everyone".

As noted by Bleacher Report, the period from the time of the injury to the July 11 fight with Conor McGregor would just be shy of three weeks.

Aldo has had a history of pulling out of UFC fights, having had to do so due to injury for UFC 125, UFC 149, UFC 153, and UFC 176. After fighting three times in 2013, the only champion in UFC Featherweight history has only fought in just one fight since.

As the news broke, a number of fighters have already taken to Twitter to put their name in the hat as possible replacements for Aldo. Urijah Faber tweeted that he's in if the dollars make sense; Jeremy Stephens tweeted, "We're calling for a reason. We hear Aldo is hurt. You know I will bring it. Let me fix the problem w/ the Irish clown"; while Joseph Duffy, the last man to beat McGregor said he's willing to step in and repeat what only two men have done in the Irishman's MMA career.