McGraw, who is touring with Faith Hill, was "super dehydrated," Hill said to the crowd in Ireland.
"He had just performed 'Humble and Kind' and got a massive standing ovation and the lights dimmed for the next song and we saw him walking across the stage and he just collapsed," a WWKA listener attending the concert said.
"Tim McGraw was suffering from dehydration in Dublin this evening at the C2C show. He was attended to by local medical staff on-site and will be fine. He and Faith thank everyone for their love and support and look forward to seeing their Irish fans again soon," a spokeswoman for McGraw said.
This is a developing story. Check back for updates.