In his illustrious career, Toby Keith has only released two radio singles he didn't write: 'American Ride' and 'Red Solo Cup.' For the country powerhouse to cut an outside song, it's gotta be pretty amazing ... or pretty ridiculous.

"It is the stupidest song I ever heard in my life, but it's so stupid it's good," Keith tells The Boot with a laugh.

The interesting thing about the song is that it was never intended to be pitched to anyone to record, but Keith heard the tune after someone who worked for him played it.

"'Red Solo Cup' is like a squirrel loose in a church house. We can play it in an office and then play five other songs, give it an hour, walk out, and you'd hear the receptionist singing it," he says. "It's like nursery rhyme stupid."

Two sets of brothers penned the viral hit: Jim Beavers and his brother Brett, and the Warren Brothers, Brett and Brad Warren.

"It's absolutely ridiculous," Jim Beavers admits to The Boot. "I can also say, having been a writer for 10 years and written hundreds of songs, I don't know a song that more people bring up in more instances than this song about a red solo cup. I don't know why, it hits something somewhere. It is the craziest, weirdest song you've ever heard."

Keith admits he wasn't sure about releasing the humorous song, but as he began to play it for people, he noticed them singing along almost immediately. So, he filmed an off-the-wall video for 'Red Solo Cup,' inviting a crew of celebrity friends to join him in the clip, including TV host Craig Ferguson, baseball great Roger Clemens, basketball icon Larry Bird and fellow music stars Sammy Hagar, Ted Nugent, Eric Church, Joe Nichols, JT Hodges, Carter's Chord, Rose Falcon and Trailer Choir's Butter, among others. And then, Keith and the songwriting brothers had something that hadn't happened in country music in a long time: a video that pushed a song into being a single.

"What I wanted to do was get 20 celebrities in it, make it like a frat party and get people to act goofy and drink. So that's what we did, and all of a sudden it's [a huge hit]," Keith says.

But the song's silly lyrics weren't Keith's only concern about picking 'Red Solo Cup' as a single.

"I was afraid since it says 'testicles,' radio won't play it," he says. "They wouldn't play 'Weed With Willie,' and this is even more extreme. But I had some radio guys tell me they would play it regardless."

The radio guys were right: 'Red Solo Cup' is certified double platinum, signifying sales in excess of two million units, and reached the Top 10 on Billboard's country charts.

The co-writers, who all appear in the music video, were thrilled with the treatment the song received.

"I don't know Toby from Adam, and I could not believe how into it he was. I couldn't believe the production he did for it," says Beavers. "I thought it was going to [have a budget of] two thousand dollars, and someone would be walking around with an iPhone doing the video on it ... I was sitting there with my brother, and I said, '[Toby Keith] made 50 million dollars last year, and he's in there acting like an absolute idiot with our song -- it's great!'"

They're also thrilled with how their silly song that wasn't even supposed to be pitched to any artists made such a huge splash.

"I have to say, it's one of the weirdest things that ever happened to me," Beavers says. "It's a Roger Miller-esque song, which we don't have anymore, so it's really cool to have something like that on the radio again."

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