Tim McGraw has arrived back in the United States following his onstage collapse in Dublin, Ireland, on Sunday night (March 11). At the airport, the country star joked with paparazzi about the incident, and appeared to be in good health.

When asked what caused his collapse, McGraw simply stated "lots of flying and dehydration" (quote via the Blast). The singer, who is known for his intense workout regimen, joked, "I gotta cut short my workouts!"

McGraw and wife Faith Hill spent the weekend (March 9-11) performing as part of the Country to Country Festival in the United Kingdom; they headlined in London, England, on Friday night (March 9), Glasgow, Scotland, on Saturday night (March 10), and Dublin on Sunday night. McGraw had just finished performing his song "Humble and Kind" during his co-headlining set with Hill when he dropped to his knees, then sat down onstage and needed assistance getting up and offstage.

"When a spotlight was switched on him, he was slumped on his knees on the lefthand side of the stage," Del Crooks, a member of the audience, tells the BBC. "The light was quickly turned off, and you could see his crew helping him off -- and the band ran over as well."

Following a break of about 20 minutes, Hill came to the front of the stage, flanked by her and McGraw's band members, and explained that McGraw would not be coming back out -- a decision made by Hill.

"So, Tim is fine," Hill told the crowd, which cheered loudly at the news. "We've all been a little bit dehydrated, traveling so much, and he's been super dehydrated, and I apologize, but I made the decision that he cannot come back out onstage.

"So drink water, people! Always keep yourself hydrated," Hill admonished the audience, which then broke into a "We love Tim!" chant. Hill and her band then performed a gospel song, "What a Friend We Have in Jesus," and concluded the set.

A representative for McGraw tells Rolling Stone that McGraw was "suffering from dehydration."

"He was attended to by local medical staff on-site and will be fine," the statement continues. "He and Faith thank everyone for their love and support and look forward to seeing their Irish fans again soon."

McGraw and Hill spent much of 2017 out on the road on their co-headlining Soul2Soul Tour, in support of their duets album, The Rest of Our Life, released late last year. In May, they will begin a 2018 leg of the trek, currently scheduled to run through late July.

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