Dierks Bentley fans who attended his first of two concert dates at Red Rocks Amphitheatre in Colorado on Monday night (Sept. 26) got a special treat. The star brought out Maren Morris for a moving duet of "I'll Be the Moon."

"She is one of my favorite singers," Bentley said of Morris, who flew in from Boston to perform. Bentley initially texted Morris to ask her to sing the song on his album. "This is my favorite song off the record."

Watch the two country acts perform the song together at the picturesque venue above. In addition to Morris, Bentley invited the Travelin’ McCourys to share the stage with him while at Red Rocks.

“We have a lot of stuff going on tonight that doesn’t happen anywhere else,” Bentley told the crowd. "Red Rocks brings everyone together ... you can’t treat this like any other show. Besides having all my fans, friends and family here, right now is a full circle moment for me. After moving to Nashville to play Country music, I walked into the Station Inn and saw these guys singing George Jones, Johnny Cash and Merle Haggard songs — but they were playing dobros, fiddles, banjos and mandolins. It was because of them that I found a foundation to build my music on."

While Morris and the Travelin' McCourys were certainly a highlight for fans, it was something that Bentley enjoyed, as well.

“There’s no other feeling like this,” Bentley remarks. “There are some big moments that happen for Country artists, and I remember one of those ... selling out the Grizzly Rose. I think it holds something like 1200 people. So we kept working hard and sold-out the Fillmore, it was amazing. And then, you get the call to play Red Rocks. Let me tell you, it’s one of those shows you look forward to your whole life. To think we’ve played here six times now and two sold out nights in a row is unbelievable."

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