The Kilmacud Crokes forward is studying international commerce at UCD and will be required to spend a semester away from Ireland in the next academic year. Rory O’Carroll completed a similar stint in France in 2011.
Mannion was a complete unknown back then, a youngster who had just made his first appearance on a county panel as a minor and his education at senior level that year came mostly from sitting on the bench with Crokes.
His rise since has been stratospheric, however.
“Absolutely,” he said yesterday. “I could never imagine the speed of it. You are not even thinking about Dublin. All you are thinking about is winning a championship with Crokes. The next thing you know you are thrown in with Dublin.”
His learning curve took in a role with the county U21s who claimed the All-Ireland in 2012 and within 15 months he was starting a senior final in front of 80,000-plus people in Croke Park.
That campaign ended prematurely with a hamstring injury but he had banked considerable game time in the nine months leading in with the U21s’ early exit to Longford allowing him stake a claim with Jim Gavin’s squad.
He was one of seven senior panellists involved last weekend when Dessie Farrell’s squad beat Roscommon in the county’s latest All-Ireland success and the likes of Mannion and Cormac Costello will report back with even more expected of them this time.
“Of course we’re always looking to improve and I suppose there’d be an expectation on us now having had a year at senior level to push on again and do more things,” he said four days after scoring eight points against Roscommon.
“It’s going to be difficult as well coming back into the squad a bit later because of the U21 championship but it can only help. It gives us that extra backup, more players, the competition for places increases.
“They’ve been doing really well. Lads like [Eoghan] O’Gara have come in and done brilliantly throughout the league, Kev Mc[Manamon], they’ve all done very well so it’s going to be a tough challenge to try and get that back.”