The young man from Donegal is visiting the US with his aunt and the pair has been sightseeing in the home of country music, Nashville.
McGee, a 23-year old UCD graduate, studied Marketing and Spanish before pursuing a career as a musician, performing at open mic nights, busking on Dublin's streets and writing his own songs.
His first stroke of luck in Nashville came when he bumped into one of his idols, Garth Brooks.
Sean Mc Gee, Diarmaid's father told The Irish Post his son was visiting the Country Music Hall Of Fame when he spotted Brooks.
"It's freaky cause he's a major Garth Brooks fan...he had two tickets for each of the five [cancelled Croke Park] shows."
Scroll down to watch the video clip...
After that stroke of luck, Mc Gee was in a UPS office trying to arrange shipping for some instruments he bought back to Ireland when he spotted a woman with a guitar.
The woman, named Morgan, works on The Bobby Bones Show radio program based in Nashville.
Sensing the opportunity, Mc Gee asked if there was any chance he could come on the show.
Intrigued by his Donegal accent and red hair, she agreed to let him visit.
Once in the studio, Mc Gee impressed with a cover of Eric Church’s song Wrecking Ball, with over 135,000 people watching the clip online so far.
Dad Sean says his son is "absolutely blown away" by the reaction. "He's busking away in Dublin and this is a major major step."
Did you catch the random Irish listener that stopped by the show and made all the girls SWOON? Here he is singing Eric Church "Wrecking Ball." WHAT!?
Posted by Bobby Bones Show on Wednesday, March 30, 2016