Despite being overwhelming favourite ahead of the bout, Conor McGregor slumped to a shock defeat against Nate Diaz at UFC 196 in March.
The Irishman, fighting two weight divisions above at 170 lbs, was undone in the second round by a rear naked choke submission.
Following the fight, McGregor said on Instagram: "I stormed in and put it all on the line. I took a shot and missed. I will never apologize for taking a shot. S*** happens."
Eight months on from his defeat and sports commentator Joe Rogan has made a shock revelation about The Notorious' condition heading into UFC 196.
According to the 49-year-old, McGregor was in bad shape and suffering from a staph injection - known to make people feel light-headed and weak - when he accepted the Diaz fight.
"He took the Diaz fight on short notice and, by the way, after a staph infection," he said.
"Here's a little thing that a lot of people don't even know. He had a pretty significant staph infection. He was on antibiotics until about two weeks before the fight.
"If you think that doesn't drain your gas tank, you've never had a staph infection and you never had to take antibiotics, they're brutal on your body."
McGregor refused to give any excuses for losing to Diaz and admirably kept his illness, which will have undoubtedly hindered his preparation, under wraps.
That's all in the past now, though, with McGregor becoming the first fighter to simultaneously hold two belts last weekend at UFC 206.
By beating Eddie Alvarez, the 28-year-old added the lightweight belt to his featherweight title.