If Ronnie Dunn can sing like this with pneumonia, then country music fans won't be disappointed when the legendary singer gets healthy for his upcoming surprise Brooks & Dunn tour.

The 66-year-old performed with his partner-in-music Kix Brooks last night (Jan. 13) at Ryman Auditorium in Nashville. The iconic country duo donated their talent to the fifth annual Million Dollar Show, a fundraiser for St. Jude Children's Hospital.

Brooks & Dunn performed three songs — "My Maria," "Boot Scootin' Boogie" and "Neon Moon" – and although Dunn announced onstage that he was battling pneumonia, he still managed to hold out some impressive long notes on their "Neon Moon" finale.

Dunn made the Nashville crowd hold their own long note for about 20 seconds before he gave it a try, and gave kudos to Music City, saying, "In Vegas they can't hold it half that time." (Brooks & Dunn have a recently extended residency in Sin City, where they perform with longtime tour mate and fellow country legend Reba McEntire.)

"I’m suffering from pneumonia and I got a cold and a headache, I’ve had a couple drinks," Dunn continued. "This is where it all goes south.”

The crowd laughed and subsequently cheered and then gave a standing ovation for Dunn's impressive finale, which included vocal runs and a few five-second-plus note holds.

The duo owned the largest ovation of the night for any of the music acts, which included Sam Hunt, Kane Brown, Brett Young and more. Brooks & Dunn made that even better by announcing their surprise comeback  tour – their first in a decade – less than 12 hours after the concert ended.

Bummed you missed the show? Check out Brooks & Dunn's tour schedule and see if the iconic duo is coming to your city in 2020.

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