Country Hall of Famer Merle Haggard's four-decade career veers into a new direction of American music with the release of "The Bluegrass Sessions," due Oct. 2 through Del McCoury's McCoury Music label.

The country giant reworked many of his previous hits for the album, including "Big City," and also tackles genre classics like "Blues Stay Away From Me."

Additionally, the album includes a duet with Alison Krauss on the newly penned "Mama's Hungry Eyes." "I really enjoyed doing it," says the 70-year-old Haggard, "and I hope this is just Volume One."

Haggard released "Last of the Breed" along with Willie Nelson and Ray Price earlier this year. After a headlining run of his own, he will join Nelson for a host of late summer shows, beginning Aug. 17 in Oklahoma City.