Steven Tyler and Bret Michaels are both doing the 'unspeakable' ... releasing a song that goes beyond their original rock 'n' roll format. And Brad Paisley thinks someone needs to put a stop to all of the madness.

"I think you have no business being on a show with an act that's not your format," he said in jest shortly after it was revealed that he would be opening the stage for the Rolling Stones in Nashville this summer. "Just who do they think they are, that they can just walk on our stage and do what they do, it's unfair."

Despite his sarcasm, it's clear Paisley disagrees with Clay Walker, who said: “We have great singers, great country musicians,” adding, “There’s no reason we have to dilute it by letting people in the format that don’t have any business being in the format.”

Country music is no stranger to pushing the boundaries into other genres. Whether it be Tim McGraw sampling hip-hop with Nelly, or Jennifer Nettles teaming up with the rockers Bon Jovi, country music and its fans have always shown Southern hospitality in accepting these out-of-towners. Paisley thinks that the same thing will happen with the latest rock transplants.

"If anybody wants to be in country, we'll welcome them, with open arms and a fair amount of skepticism," the star jokes. "But then you got guys like Darius [Rucker] who just blow the doors off, so we're certainly wide open to it."

Paisley will push boundaries out of country himself when he opens for the Stones on June 17 in Nashville at LP Field. This summer, he will also play LP Field during CMA Music Festival as well as continue the Crushin' It tour alongside Justin Moore and Mickey Guyton. But in the meantime, Paisley has high hopes for Tyler.

"It'd be fun to see Steven Tyler have success in this town. You know, how much fun would that be to hand him a CMA award for something?"

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