Joe Nichols and Blake Shelton have a mutual admiration society going on, and a friendship that stems all the way back to the days they spent together over a decade ago on a now-defunct record label. Both singers experienced their share of struggles before making their mark on Music City, so for Joe, it's been especially satisfying watching buddy Blake's star rise over the past few years.

"We've been friends since '98," Joe tells The Boot. "We were both on Giant Records back then, or as we like to put it, we were both in the 'Artist Protection Program.' It was way back in the day, and we had a lot to gripe about. But we had a lot to be thankful for back then, too, and we'd spend a lot of time wondering what, if, and when's it gonna happen for us. I'm proud it's just exploded for him. If there's anybody in country music that deserves to be heard, it's Blake. The guy's got a great voice, he's got a great ear for songs, and my God, that guy's a hoot! I don't know anybody with a better wit than Blake. He's a funny guy, and country music needs personalities. We've got a lot of voices, and a severe lack of personalities. But he's one of those guys whose personalities you've gotta like!"

Blake is a card-carrying member of Joe's fan club as well, and cites him as one of the reasons he moved to Nashville in the first place. "I'm a huge Joe Nichols fan," Blake tells The Boot. "If he puts out a record, I'm one of the first people pushing old ladies over at Walmart to get one. I'll punch 'em if I have to. [laughs] I love Joe, and I've known him for years. It's beyond just a friendship. I'm a fan of his voice and just what he does. He's got this thing about him that takes me back to why I wanted to do this to begin with [and why I moved to Nashville]."

The two friends are not only big fans of each other's music, they apparently have similar taste in material as well, since one of Blake's recent No. 1 hits, 'Who Are You When I'm Not Looking,' was actually a song Joe recorded a few years ago for his 'Real Things' album. Joe admits that although he was disappointed he didn't get to release the song as a single, he's thrilled Blake made it the hit it deserved to be.

"'Who Are You' is one of the mistakes you make along the way; the woulda, coulda, shoulda that has happened, and you just wished things would've been different," says Joe. "When we cut [it], I begged for that to be a single, for that to be the first single. But a lot of people who get paid a lot more than I do make a lot of the calls, and it didn't go my way. The one thing I am proud of now is that it found a home with Blake. It's the hit it should've been, and I'm glad he's the guy that cut it."

Joe and Blake will both be working on New Year's Eve. Joe has joined the lineup for FOX's 'American Country New Year's Eve Live' (Saturday, Dec. 31 at 11:00 PM ET) and Blake will join Carson Daly for NBC's 'New Year's Eve With Carson Daly,' live from New York's Times Square beginning at 10:00 PM ET.

Watch Blake Sing 'Who Are You When I'm Not Looking'

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