Garth Brooks playing a free show at Ascend Amphitheater on Mon. (Oct. 24) was exciting enough already, and now he’s added another star to the guest list.

Brooks invited "Think of You" singer Chris Young to perform with him at the celebratory concert via Twitter on Thursday (Oct. 20).

The star-studded show serves as a celebration of the country superstar’s seven diamond-certified records -- the first artist in history to do so. While the event is sold out, Brooks has been giving away tons of free tickets via Snapchat to some very lucky fans.

The free concert was announced this month at a press conference with Brooks and Governor Bill Haslam as a partnership with the Tennessee Department of Tourist Development to celebrate the singer’s historic achievement.

Brooks hit another milestone on Tues. (Oct. 19) when he announced that his music is now available for streaming on Amazon Music, making him the first seven-diamond certified singer to use the service. He also recently announced the name of his upcoming album, Gunslinger, which will be released on Nov. 25. The lead single from the new project called "Baby, Let’s Lay Down and Dance" debuted on Oct. 13.

Brooks takes over Ascend Amphitheater on Mon. (Oct. 24) at 7PM. For more information on Brooks' new album, single and more, visit his official website.

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