Heavyweight boxing champion Andy Ruiz Jr. knows the feeling of dealing an undefeated boxer his very first loss following that upset he pulled on Anthony Joshua last month. To recall, the underdog won via TKO in the 7th round against AJ, making him the undisputed WBA (Super), IBF, WBO, and IBO heavyweight champion.

Ruiz was in attendance to witness Manny "Pacman" Pacquiao's split decision win over Keith "One Time" Thurman at the MGM Grand in Las Vegas last weekend alongside other popular names in the boxing world. And similar to most post-Pacquiao fights, a rematch with Floyd Mayweather Jr. was up in the air. The first Mexican to become heavyweight champion was asked for his take on the potential rematch and Ruiz believed Pacquiao had a good chance of winning.

"I think Manny because he's been more active," said Ruiz in an interview with TMZ Sports.

Seeing how he defied the odds to pull the rug from under Joshua, the 29-year-old may have a valid point. However, he is not discounting the fact that Mayweather would win once more after pointing out how the Flamboyant one manages to keep himself in shape and has a good track record in the sport.

"Mayweather is Mayweather. He's always good. He stays in shape, takes care of himself ... but it would be an awesome fight," he added.

Ruiz' take comes not long after both Pacquiao and Mayweather traded barbs on social media. Mayweather once again reiterated that he has no interest in a rematch with Pacquiao via his Instagram account. It did not take long for the eight-time division champion to respond and point out how the undefeated American boxer was using his name to stay relevant on his Twitter account.

As for Ruiz, he is preparing for a rematch of his own against Joshua. AJ had a rematch clause on the contract of the first fight. However, promoter Eddie Hearn that it will be Joshua who will say when the rematch will take place, Boxingscene.com said. Joshua is looking for retribution while Ruiz is out to prove that his 7th round stoppage last June was no fluke.