Pacquiao Vs Marquez
Manny Pacquiao last won a fight when he defeated Juan Manuel Marquez on Nov.11, 2011. Reuters

Juan Manuel Marquez steroid rumors are spreading as the boxing community continues to wrap its collective head around his stunning sixth-round of archenemy Manny Pacquiao on Saturday.

Doping is a part of the sporting world, from baseball to biking to baseball, whether we like it or not, and Marquez's massive KO against Pacquiao is just the latest in a seemingly endless stream of questions about whether athletes are juicing in the modern age.

The Juan Manuel Marquez steroid rumors are based in a number of circumstances which combine to lend credence to jaded boxing enthusiasts' assertion that he had to have been on performance-enhancing drugs during the Pacquiao fight.

One root of the juicing rumors swirling about Marquez in the wake of the crushing sixth-round right that left Pacquiao face-down on the mat is Marquez's appearance during the marquee bout.

Marquez, who is a ripe 39, looked stronger than any other time in recent memory, and that caused the New York Daily News to ask how such an aging giant could show “up for this fight bigger and brawnier than ever — even though he is at an age when athletes find it hard to build muscle.”

And the Daily News didn't stop there. It also touched on another key root of the steroid use rumors that are now following Marquez in the wake of his epic win.

That root goes by the name Angel Hernandez (formerly known as Angel “Memo” Heredia), a former steroids dealer who has been connected with previous PED use by athletes. For his part, Hernandez told the Ring in November that Marquez was clean. By that point the steroids rumors were already cropping up in conversations about the star fighter and his bulky appearance.

"You know, the public opinion is always going to be there. You as an American can also have an opinion, but as we said earlier, we were the first ones who said that we are not using anything illegal," the trainer said. "It doesn't make me angry, because they can always have the opinons they want. We don't have to hide. I've always been open with the press. I don't have to be afraid of anything. I'm very happy to be here."

Marquez himself also spoke with The Ring about the doping allegations: “I think that you can say anything that you want, but you don’t have any proof, so what does that mean? It means nothing.”

Marquez on Monday addressed the steroid accusations in a conversation with the Los Angeles Times. "I am a clean fighter," he asserted, adding that drug tests in Nevada will prove it. "I feel very happy with my training, I feel great about the tests ... I won’t have a problem.”

The Ring columnist Ryan Rudnansky, for his part, seems to wish that the inevitable controversy over doping did not have to play into what was likely the fight of the year.

“I agree that Marquez was asking for trouble when he hired Hernandez, because he had to realize Hernandez would be exposed at one point, but for people to jump to conclusions doesn't give Marquez the credit he deserves,” Rudnansky wrote on Nov. 5. “He hasn't won so many fights because he's the strongest or fastest in the ring; he's won because he executes his counter-punching style masterfully.”

Freddie Roach, Pacquiao's trainer, even went so far as to suggest to USA Today before the fight that Marquez had used some form of PEDs in order to get in the shape he was in Saturday night.

"If [Marquez's body] is natural, I will kiss his a--," Roach told USA Today.

Roach is not the only skeptic either, though he may be the most prominent.

It doesn't appear there will be an end to the controversy over whether Marquez – or Pacquiao for that matter – was on steroids or any other illegal substances during Saturday's fight, as neither submitted to a drug test before the fight, the Daily News reported. That's because boxing doesn't require them to do so, and neither volunteered to do so.

So as the steroid rumors continue to fly in the wake of the Marquez-Pacqiao showdown, they will likely remain just that – rumors.