B.J. Penn and Rory MacDonald Get into It on Twitter

You know how sometimes mixed martial artists like to hurl insults and challenges at one another before a fight?

Well, it looks like B.J. Penn vs. Rory MacDonald, a bout scheduled for UFC on FOX 5, is going to be one of those times.

MacDonald kicked things off by expressing his physical superiority over Penn, Tweeting a picture of himself all buffed up, with the following caption:

"

200lbs and @bjpenndotcom thinks i care if hes in shape for the fight or not

"

Not one to let an opponent flap his gums without receiving an earful in return, Penn logged onto his account and Tweeted the following response:

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@rory_macdonald Great!!! I frekin love knocking out 200 pounders

"

Things didn't end there. In fact, they were just kind of getting started. 

MacDonald responded to Penn's boast by taking a jab at the Prodigy's infamously underwhelming physique.

"

@bjpenndotcom do u meen knockin back quarter pounders? Who r u kidding, certainly not yourself ?

"

That's about the time things devolved into a grade school exchange. Penn fired back at the defamation by targeting MacDonald's bacne (back acne).

"

@rory_macdonald Quarter pounders?? Really pimple boy? I won't even RNC you... afraid of all the pimples on your back. #GROSS

"

As of now, MacDonald has scored the last word, reiterating that he views Penn as a less than threatening opponent.

"

@bjpenndotcom i didnt think it was possible but somehow u made yourself even less of a threat

"

Truly, UFC on FOX 5 will not be just another card featuring top mixed martial artists. No folks, we have entered the epic realm of legendary warrior poets.