One year after Merle Haggard received the Crystal Milestone Award, the legend was front and center at the ACM Awards again, at least in spirit. Eric Church and Keith Urban teamed up to open the 2015 ceremony with a medley of Church's "Pledge Allegiance to the Hag" and their own duet "Raise 'Em Up."

"Pledge Allegiance to the Hag" was a track from Church's 2006 album Sinners Like Me that mentioned the country legend by name. The shoutout to one of the all-time greats made sense, given that this year marks the 50th anniversary of the ACMs.

Church and Urban both played their electric guitars as they walked out into the crowd. When the two men found their way back to the stage, they switched into a passionate performance of "Raise 'Em Up," harmonizing in front of a wall of video screens depicting lighters waving in the sky.

Haggard won the Academy's first Entertainer of the Year Award and captured Male Vocalist of the Year six times in his career. He did not appear to be in the crowd, but other big names were, including Taylor Swift and Reba McEntire, who danced along with the performance.

Church and Urban are both nominees tonight, with Urban competing for Video of the Year and Church appearing in three categories, including Album of the Year, for The Outsiders.

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