When Nate Marquardt got popped for elevated levels of testosterone and later revealed his history of usage, there was no shortage of fighters that wasted little time in calling him out.
The list of notables included Bellator champions Ben Askren and Hector Lombard, who both called him a cheater and begged him to sign with their promotion so they could do their dance.
But there was another, much bigger, name that went after Nate as well -- former UFC Lightweight and Welterweight Champion B.J. Penn.
Hawaii's son went on a Twitter crusade and called for the removal of "PED cancer" from MMA shortly after word leaked that Marquardt had been busted. And while he didn't specifically name him, it was clear just exactly who he was talking about.
Well, Marquardt was listening and he's not happy about the many people that chose to kick him while he was down.
As with most feuds these days, it's gone to Twitter and both men are getting after each other and, presumably, holding nothing back. Here it is:
Penn comes out heavy and straight up tells Marquardt he'll come to his gym to settle things ... on one condition:
"I'll show up to your gym to fight if you do a drug test every week for 3 months. Winner Keeps the video. Lmk (:"
To which Marquardt responded:
"How about I give u my most recent and another one now showing that it's low and I still mop the floor with your midget head?"
Nate would go on to tell a fan that he would "make him quit like GSP did."
Get low, gentlemen. Get low.
"The Prodigy" wasn't done, though, and finished off the mini-Twitter feud with these parting words:
"What a Joke! 1 drug test? lol.. You should be tested every week for 3 months... and then we 'll fight. ... I have no doubt I will beat you if you come in natural like i have been doing my entire career."
It's unfortunate that Marquardt has been cut from the UFC, as there is no place better to settle a score than inside the Octagon in front of thousands of screaming fans.
And Marquardt had just moved down to welterweight, while Penn made the jump up to it. Oh, what could have been and will likely never be.
Whose side are you on?