Former UFC bantamweight champion Pena won the pair’s first meeting at the T-Mobile Arena in Las Vegas last December, submitting Nunes in the second round of their bantamweight showdown.
But the Lioness exacted revenge on the American seven months later at UFC 277, winning a five-round war via unanimous decision.
McGregor and Diaz meanwhile took part in two of the most memorable fights in MMA history six years ago.
And The Notorious was quick to point out the obvious similarities between Nunes-Pena and that of his own rivalry with Diaz.
McGregor said on Twitter: “It’s mad to me the similarity of last night’s ladies bantamweight world title rematch to the McGregor-Diaz fights.
“Fight number one, the highly touted, the GOAT of the sport, me, Amanda Nunes, just sheer toughness, willingness to fight and caught off guard.
“Gives a couple of shots, then eats a couple of shots, then the tide turns, then gets choked.
“Now the return, the rematch, confidence on the other side, tenacity, toughness, all that still there. More focused work on Amanda Nunes’ side, my side.
“And the reason I’m saying this is because I’m a huge fan of both those women, I’m a huge fan of Amanda Nunes and Julianna Pena, and everyone that steps inside that octagon to be honest and makes that f***ing walk.
“But at the end of the original bout, ‘I’m not surprised, motherf******,’ and then again, ‘I’m not surprised, motherf******,’ Julianna says it.
“And then, the fight goes the exact same way in the second fight. Dropped multiple times, just better prepared, cracks the shots, gets the drop multiple times. But then the toughness is still there, still in Amanda’s face, still in my face.
“Some fights they are. They’re iconic mixed martial arts bouts that we’re all lucky to witness. And it’s mad that, you know, double champ, double champ, ‘I’m not surprised, ‘I’m not surprised’. I don’t know, it’s a madness I’m seeing.”
Both McGregor and Diaz are currently riding two-fight losing streaks, with the former suffering back-to-back defeats to Dustin Poirier and the latter having lost to Leon Edwards and Jorge Masvidal respectively.
However, a series decider between the pair is under serious threat as Diaz is reportedly on the verge of leaving the world’s premier mixed martial arts promotion.
And while a trilogy fight is still high on many fans’ wishlists, UFC president Dana White says he won’t lose sleep if it never comes to fruition.