UFC featherweight champion Conor McGregor is "unlikely" to compete at UFC 205 on Nov. 12 in New York, according to a report from "UFC Tonight."
Wednesday's report stated McGregor is "rehabbing a leg injury."
With this announcement, the UFC 205 pay-per-view remains without an official main event.
Even so, the UFC has announced a press conference on Sept. 27 at Madison Square Garden. The event is historic for the promotion in that it will be the first held in New York since a 1997 ban on professional mixed martial arts was lifted earlier this year.
McGregor was visibly limping following his decision win against Nate Diaz at UFC 202 in August, but sources close to the Dublin fighter told ESPN.com he is "fine" and physically ready to compete within the time frame leading up to UFC 205.
Current UFC lightweight champion Eddie Alvarez (28-4) has been campaigning for a title fight against McGregor (20-3) at UFC 205. McGregor posted a cryptic tweet early Wednesday morning with the words, "Beg me."
Earlier this week, however, UFC president Dana White revealed via social media that the UFC was looking to book Alvarez to a title fight against Khabib Nurmagomedov (23-0).
According to the "UFC Tonight" report, which attributed the information to White, Alvarez was sent a bout agreement for the proposed Nurmagomedov fight at UFC 205, but Alvarez did not sign by a provided deadline.
The UFC is now looking to book that 155-pound title fight at UFC 206 on Dec. 10 in Toronto. Representatives for Alvarez did not immediately respond to requests for comment.
Alvarez won the lightweight championship in a first-round knockout over Rafael dos Anjos in July.
McGregor remains the UFC's featherweight champion, for now. He won the belt in December, by knocking out Jose Aldo at UFC 194.
Nurmagomedov (23-0), a fighter from Dagestan, is eager for Alvarez to sign on the dotted line.
Nurmagomedov told ESPN.com via text, "Before, I have big respect for Eddie Alvarez. Now, I don't. He embarrasses his camp, he embarrasses his fans. UFC 206, I'm going to embarrass him."
