If Dan + Shay want to perform, you better believe they are going to do so ... even if their concert gets canceled. The country duo turned a last-minute show cancellation into a special night for some of their biggest fans on Friday night (Sept. 14).

Dan + Shay have spent their summer out on the road with Rascal Flatts, on the Flatts' Back to Us Tour. The trio's Gary LeVox got sick, forcing the cancellation of the trek's Friday night stop in San Diego, Calif. -- so, Dan + Shay decided the show must go on and quickly booked a set of their own at San Diego's House of Blues.

A press release reports that Dan + Shay's pop-up show sold out within an hour. Dan Smyers and Shay Mooney also called the fans who had meet and greets for the original show to invite them to the new venue. Readers can press play above to see some footage from the House of Blues show.

LeVox's illness also prompted the cancellation of Saturday night's (Sept. 15) Back to Us Tour stop in Irvine, Calif. The trek is scheduled to wrap up on Thursday (Sept. 20); from there, Dan + Shay will join Chris Young for the fall portion of his Losing Sleep Tour.

Dan + Shay recently released Dan + Shay (The Vocals), the vocal-tracks-only version of their newest album. The collection of songs is available for download and streaming on various platforms.

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