Nathaniel Rateliff and Friends' closing set at the Newport Folk Festival on Sunday opened with a surprise guest -- Dave Matthews.

Matthews played six songs by himself to open the set, then was joined by Brandi Carlile to duet on a new song called “Papertown.” Rateliff and his house band then came out to join Matthews on another new song called “Flowers.”

Rateliff was joined by The Killers' Brandon Flowers for a cover of John Prine’s “Paradise,” and Mavis Staples came out for a cover of Kevin Morby’s “Beautiful Strangers.”

Flowers returned for a cover of Bruce Springsteen’s “Atlantic City” and Matthews came back out for a cover of The Band’s “The Night They Drove Old Dixie Down.” The set ended with all the day's guests on Bob Dylan’s “I Shall Be Released” and “America the Beautiful."