Melvin “The Young Assassin” Guillard hasn’t exactly been slaying the competition lately.

The veteran of The Ultimate Fighter Season Two has enjoyed some memorable career highlights — including this prank of UFC President Dana White on the TUF2 show, with the help of coach Rich Franklin:

He also enjoyed some success in the cage, including a five fight UFC winning streak from 2010 to 2011.

But lately, he’s been far from the killer of old — having managed only three wins in his last nine bouts.

And now, it looks like he may be cutting his own throat, as far as his career goes with his latest employer, MMA World Series of Fighting.

Guillard, whose career record stands at 32-14-2 (with two no-contests) weighed in four pounds over the lightweight limit for his last WSOF appearance, a loss to the promotion’s lightweight titleholder Justin Gaethje.

Then, last week, Guillard inexplicably trashed WSOF in an interview on Submission Radio:

“To be honest, instead of being the World Series of Fighting champion I’d rather be in the UFC just fighting in the top 10 and probably never becoming the UFC world champion, if I had that option… If I had the option to be the World Series champion right now, or go back to the UFC to finish off my career with the UFC, whether I get a title shot or not, I would take that UFC contract over a World Series [contract] any day.”

Back on Monday, WSOF announced Guillard was off this weekend’s WSOF 20 show, having not turned in his required medical reports in time.

Yesterday, WSOF President Ray Sefo explained the matter at a press event, as transcribed by Heidi Fang of MMA Fight Corner:

“He missed weight for a world title fight. He put us at risk in terms of, I mean, what happened if he won that fight? And then, our PR team has reached out to him and his management team several times to do PR, and he completely ignores that. And then he goes off and does his own interview with somebody else and trash talks the company. I’m not going to tolerate that kind of behavior.

“And then, he was given a deadline which was going to be last Friday for his medicals and that didn’t happen. And then, Ali [Abdel-Aziz] sent out an e-mail saying that if he doesn’t have his medicals by 10 o’clock Monday morning, then he was going to be pulled from the card. And I think 10, 11, 11:30, 12, we still hadn’t heard anything from his management team, nor had we heard anything from him.”

“I’ve been in this game for a long time. I’ve had 101 fights and there’s not one time that I was unprofessional in any fight, even when I was an amateur. And again, I’m not going to tolerate anybody that’s going to be unprofessional when we’re doing everything we can to try and help you.”

WSOF 20, headlined by a light heavyweight tournament semifinal between Dave Branch and Ronny Markes, airs this Saturday at 9 pm ET on NBC Sports Network.