Fans who saw Eric Church perform at the American Roots Music and Arts Festival in Raleigh, N.C., on Oct. 18 got to witness a once-in-a-lifetime stage performance when two very special guests joined him onstage.

Allman Brothers Band and Govt. Mule guitarist-singer Warren Haynes and country singer Joanna Cotten sat in with Church for a very special rendition of "The Weight," the classic song from the Band's seminal 1968 debut album, Music From the Big Pink. Written by Robbie Robertson, the song has often landed on critics' lists of the most influential songs of all time.

Clad in a leather jacket, sporting his trademark sunglasses and playing acoustic guitar, a beaming Church infused the song with a genuine blues feel, displaying a side of his voice that his own music does not usually allow for. He took the first verse solo, and was joined by Haynes and Cotten for the chorus harmonies. Haynes also contributed tasteful slide and single-note blue runs before taking the second verse for himself, to Church's obvious delight.

Cotten delivered a scorching solo vocal on the song's third verse, but perhaps the high point of the performance was Haynes' slide guitar solo spot in the middle of the track, which showcased his exceptional control and tasteful melodic sense. Church and Haynes each took another verse before the three brought the six-minute performance to a rousing conclusion, drawing a huge ovation from the festival crowd.

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