The Guardians of the Galaxy star came out during the tail end of Stapleton's set at Bridgestone Arena and greeted the surprised crowd. Clad in a Chris Stapleton jacket, he excitedly greeted concertgoers before taking the microphone alongside the country star and his equally talented wife, Morgane. You can see a full clip of the moment above.
Although it may seem like a random choice, Stapleton and Pratt have publicly shared their admiration for each other over the past year. After Pratt name-dropped the singer as one of his favorite artists in multiple interviews, Stapleton sent him a customized mixtape.
Many fans were eager for a surprise appearance from Justin Timberlake, who showed up at the pop star's festival slot in Franklin, Tenn. last month. However, Timberlake was out of town during both of Stapleton's arena gigs. It's unclear what Pratt was doing in Nashville, other than enjoying some time taking in one of the best voices in the Music City. But you have to give him props for being brave enough to sing his heart out alongside two of country's most impressive performers.