Chris Young's crew knew Kane Brown was there. His crowd knew it, too, but somehow the singer was the last to be let in on a big surprise in Pennsylvania on Sunday night (Aug. 29).

Prior to Sunday, Brown and Young had never shared a stage to sing their chart-topping hit "Famous Friends," and Young didn't plan on it happening that night, either. Video shows Young beginning the second verse — the verse Brown sings on the record — but showing some confusion as the thousands in front of him start screaming.

Watch for yourself:

The moment took place at Citadel Country Spirit, a three-day festival that also featured Brantley Gilbert and Miranda Lambert. Fans on Twitter shared video from the crowd, as well. Young looks to double over laughing, clearly having no idea that Brown was waiting in the wings.

While they've performed the song on television — and Young once surprised Brown to sing it during a concert — this was the first time Brown has surprised Young.

The song is the title track from Young's new album, released earlier this month which also features collaborations with Mitchell Tenpenny and Lauren Alaina. Talking to Taste of Country, Young says that he's intentional about putting himself alongside powerful vocalists.

"I love singing next to someone who can sing. The whole time I’m like, ‘You better not mess this up,'" Young says, laughing during a recent media Q&A. "Even if I got one of those days where I’m on the road and you’ve been out for months … it’s like ‘Why did I do this to myself again?’ Who cares? Because they’re fun to sing and I do like standing on a stage next to someone that’s as vocally talented as somebody like Lauren and getting to sing with her."

Young and Tenpenny actually begin the Famous Friends Tour in October, while Brown embarks on his Worldwide Beautiful Tour later this week.

After the song, the two friends shared a hug for the ages.

Top Country Songs of 2021, Ranked

You'll find much more than just the Top 10 Country Songs of 2021 on this list.

Our team has sourced fans to create 10 superlatives for this mid-year version of the year-end songs list. Best Country Tearjerker? Best Country Baby-Maker? Best Country Breakup Song of 2021? Keith Urban, Carly Pearce, Chris Bandi and more help make up this portion of the Top Country Songs list, while hitmakers like Thomas Rhett and Little Big Town lead the 10 best songs portion.

Did your favorite song of 2021 make this list? To be considered, the song must have been released in 2021 or have actively charted for a portion of the year (see "Wine, Beer, Whiskey"). New artists including Lainey Wilson, Breland and Triston Marez crack the Top 10. Let us know your favorite song of 2021 at Twitter or email, at staff@tasteofcountry.com.

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