Former Ultimate Fighting Championship featherweight champion Jose Aldo accused Conor McGregor of using banned substance before their title fight at UFC 194 in December last year.

Aldo, who was knocked out just 13 seconds into the opening round of the bout, said that McGregor was "full of juice" before their showdown but had a lot of chance to clean up his system to avoid facing disciplinary actions.

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"He was full of juice in his body, where he hides and nobody tests him, only when he gets to Las Vegas, a week before the fight, and then it is way easier for you to clean the body and fight," Aldo said via MMA Fighting.

Aldo also revealed that UFC asked him to step in for Rafael dos Anjos, when the UFC lightweight champion was forced to withdraw from his UFC 196 showdown with McGregor. The Brazilian featherweight superstar said that he did not accept the bout because it will not be a featherweight showdown and he was not prepared at all.

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Aldo, who held the UFC featherweight title for five years, said that if McGregor was really willing to face him, he could have agreed to a rematch days after their UFC 196 showdown.

The 29-year-old also blasted the decision to give McGregor an immediate rematch with Nate Diaz at UFC 200.

"He will be fighting at the same night in a different division, in a rematch that means nothing," Aldo added. "We asked for a rematch. For everything I've done, all the years as champion, I deserved a rematch, but what can I do? I had to accept. We're not the ones making the call."

Following UFC's decision to stage the McGregor-Diaz rematch, Aldo accepted the fight against Frankie Edgar for the interim featherweight title. Aldo is not giving importance to the "interim" tag, but he vowed to go all out in order to move a step closer to getting another crack at McGregor.

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