Vince Gill's newest album is a tribute to the music of Buck Owens and Merle Haggard. But in a new interview, he admits to some trepidation about singing such classic songs -- especially Haggard's, since the legendary musician was such a vital influence on him.

Gill collaborated with Nashville steel guitar ace Paul Franklin for 'Bakersfield,' which they released Tuesday (July 30) via MCA Nashville. The album features their faithful versions of classics including 'The Bottle Let Me Down,' 'I Can't Be Myself,' 'He Doesn't Deserve You Anymore' and 'But I Do.'

"As a singer, it's a daunting task to have the guts to take on any of these songs. It's almost foolish," Gill tells Billboard. "I like a good challenge, and I love the way that when I sang Buck's songs or Merle's song, I honored the way that they sang. I phrased like they did a little bit, and with Merle's songs, he had more of a crooner side to his style than Buck did."

He adds, "He's my absolute favorite in all things -- musician, singer, songwriter, and all those things wrapped up in one, I don't think anyone has ever touched Merle Haggard to the degree of his greatness."

Haggard likes the album so much that he volunteered to write the liner notes. "It's better than anything I could describe," Gill states. "I just hope he's not pulling my leg. I've always been so influenced by him. It means the absolute world to me that he heard it, and we got a double thumbs up."