Alison Krauss

It was announced on Friday afternoon that Nelson would be taking a few days off per doctor's orders.

Live version of the Led Zeppelin classic is the duo's first official release in two and a half years.

Country legend Willie Nelson's Outlaw Music Festival will return to Pine Knob in Clarkston on September 15, along with Bob Dylan and John Mellencamp.

The trek begins June 2.

Gov't Mule, the Avett Brothers and many other acts will appear on various dates.

Duo adds 13 stops to itinerary, keeping them on the road through September.

Track was made famous by Lucinda Williams in 1998.