CMA Fest 2019 began Thursday (June 6) in Nashville, and the stars wasted no time in bringing their A game. From the free daytime stages to the big shows at Nissan Stadium, great music -- and plenty of special guests -- was everywhere.

Marty Stuart's last-minute cancellation of his Nissan Stadium show due to a "personal family matter" made room for Tanya Tucker to fill the schedule gap, with collaborator Brandi Carlile in tow. Brothers Osborne brought out both Brooks & Dunn and Ashley McBryde during their set, while CMA Fest host Kelsea Ballerini came armed with the Chainsmokers. Florida Georgia Line, meanwhile, invited Morgan Wallen and Hardy to the party.

During the day itself, sets from Lindsay Ell, Jimmie Allen and Runaway June, among many others, gave fans in town for the big event plenty of live music to hear. Hundreds of country artists will perform during CMA Fest 2019's four days; the event runs through Sunday (June 9).

Want to see more of the fun from CMA Fest 2019's first day? Flip through the photo gallery below.