© Jeffrey Swinger-USA TODAY Sports

Conor McGregor isn't the only superstar returning to the Octagon this year.

That's right, UFC Hall of Famer Jose Aldo is coming out of retirement for another fight at UFC 301 in his backyard of Rio de Janeiro, Brazil. The former featherweight champ meets rising contender Jonathan Martinez at bantamweight. 

'The King of Rio' retired from MMA less than two years ago, but he's kept active in boxing with three fights since then, one being a majority draw against former UFC foe Jeremy Stephens.

McGregor, who dethroned Aldo to become the UFC Featherweight Champion in 2015, is beyond delighted to see his old rival trade the ring for one more run in the UFC.

"Look at Aldo now. Great to see Jose back," McGregor said on 'The MMA Hour'. "Really happy to see Jose back."

We last saw Aldo compete in the Octagon against current #1 contender Merab Dvalishvili in what was likely a title eliminator for the Brazilian fighter. 

Aldo put together three straight wins over Chito Vera, Pedro Munhoz and Rob Font and was high up in the rankings before he suffered a unanimous decision loss to Dvalishvili. 

Despite showing he could still hang with the best bantamweights in the world, the UFC veteran laid down the gloves not long afterwards, a move that puzzles McGregor to this day.

"I was actually taken back why he did retire when he retired. He was a contester for the f****** title," McGregor continued. "He was in title contention from what I was looking. He was very unlucky not to even scoop the title and he fought the champions and whatnot. 

"I'm happy to see Jose back. I wonder, was it a finance, was it a business play that didn't play out for him? I wonder was he trying to press for something more or something like this and then walked away? And then they just let him. And then they kind of, you know, he went and done his boxing matches and all the rest of it and whatnot. But now he's back, excited to see him back. Tremendous goer. Always great for the company."

From an idol to a rival, UFC Bantamweight contender Jonathan Martinez is ecstatic for the chance to welcome Jose Aldo back to the Octagon.

"I was a fan, I used to watch him.” Martinez said of Aldo, told MMA Today (h/t BJPenn.com). “My parents used to watch him when he was in the WEC. I wanted to fight him before he retired too, but then he retired. That was it. Then one day they asked if I wanted to fight him and I said yeah, I didn’t hesitate at all. I said yeah, let’s do it.”

Watch Jose Aldo's return fight against the up-and-coming Jonathan Martinez on May 4 at UFC 301.

If you use any quotes from this article, please leave an H/T to MMAKnockout.com for the transcription.

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