Fans who attended Ashley Monroe's headlining gig in Nashville on Friday night (Nov. 20) got more than their money's worth when Miranda Lambert joined her friend onstage for a special duet.

Monroe performed a sold-out show at City Winery in Music City to promote her critically acclaimed sophomore solo album, The Blade. According to The Tennessean, the gig was the biggest sell-out the venue has ever had, but it got even bigger when Monroe announced, "I just released a record this year called The Blade, and I'm gonna do that song, and I'm gonna have the special guest vocalist that sang on that song on the record with me sing it, for the first time live, really, ever. So ... here's little miss Miranda Lambert!"

The audience applauded and cheered wildly as the CMA Female Vocalist of the Year took her place on stage next to Monroe, no longer sporting the pink-tipped hair that she debuted at the CMA Awards earlier in November. The pair delivered a strong version of the emotionally hard-hitting song, joining their voices in harmony at the chorus like the old friends and singing partners they are.

Lambert also lend her support at the release party for The Blade in July, joining her friend and Pistol Annies bandmate live for "Heart Like Mine" just days after she announced her divorce from Blake Shelton, and Pistol Annies surprised fans with an impromptu reunion onstage at one of Lambert's concerts in October. Monroe says a full-blown reunion is "brewing."

“We have a lot of song ideas going. I feel like it’s soon,” she tells Fuse.

Check out Monroe and Lambert's performance of "The Blade" in the video above.

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