It doesn't appear that Motley Crue's Nikki Sixx and Godsmack's Sully Erna are going to be BFF's anytime soon.

Godsmack had reportedly requested to appear on Sixx's 'Sixx Sense' radio show to promote their new record. Sixx's response to the request, sent via Twitter, was anything but subtly worded:

Ouch.

In case you're wondering how things got sour between the two, here is a little history lesson for you:

In the summer of 2009, Godsmack were one of the acts on Motley Crue's 'Crue Fest' tour. Erna was reportedly less than impressed about his perceived treatment of the band and took to the press to air the dirty laundry. It is also heavily rumored that the track 'Cryin' Like A B---h' from Godsmack's 2010 album 'The Oracle' was written about Sixx. The lyrics read, in part, “Strut on by like a king / Telling everybody they know nothing / Long lived what you thought you were / Time ain’t on your side anymore.”

After discovering he might be the subject matter in the song, Sixx addressed the matter, stating, "Every person — from road crew, fans and even all the bands on the tour (including [Sully's] band) — was so happy, but [Erna] just seems to be crying like a b--h. Funny, even his manager told me he’s an a—hole. Maybe the problem is just in HIS head… I got no problem with him.”

During a radio interview in August 2011, Erna danced around the question as to whether or not Sixx was the target of the song. Perhaps most tellingly, he did not deny the song was about the Motley Crue bassist:

“It’s very difficult for me to restrain myself from answering that question because as honest as I’d like to be, the other side of me doesn’t want to give anybody the extra exposure, even if it’s negative. So, I’m just gonna plead the fifth.”

Refusing to let sleeping dogs lie, as Motley Crue were preparing for their Las Vegas residency in January of 2012, Sixx tweeted “We’re looking for an angry midget for our Vegas shows and were thinking of using the singer from Godsmack.” This past December, Sixx once again targeted the Godsmack singer via Twitter, sending out this tweet: “RIP Sully Erna … Oops, I’m sorry, I meant your career.”

So far, Erna has not publicly responded to Sixx's comment.

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