Mulligan was the deserved recipient of the prestigious award following a string of influential displays at the heart of the Crokes midfield en route to their first championship success in 27 years.
He said: "I'm absolutely chuffed with the award although, to be honest, it was totally unexpected. It's a very nice way to cap off the year and it was a good year for the club and for me personally."
Mulligan's recognition was influenced by Kilmacud finally realising their potential after a number of disappointing campaigns, and the midfielder puts his side's improvement in fortunes down to a more professional and hard-working attitude.
"I think this year, more than any other, we emphasised the importance of our work ethic and that we would give our all at every opportunity.
"I think that is something that was possibly lacking in previous years. That drive and ability to go for every ball may have been missing and we made sure that every hook and block was done with the best intensity possible," he said.
Of course, many observers expected Kilmacud to arrive at the top table far sooner than they did, given the quality of talent emerging from the juvenile and minor set up.
Mulligan was one of the many protégés to make his mark this year and it was the influx of this youthful enthusiasm that added an extra edge to Crokes' championship ambitions, according to the UCD student.
"Some of the younger lads like Jack Doughan, Sean McGrath, Bill O'Carroll and Jude Sweeney showed a lot of leadership this year and they put in some serious performances.
"There was a nice blend of the younger lads coming through who stepped up to the plate and a lot of those have genuine intercounty experience to add to our more senior players like Ross (O'Carroll), Ryan (O'Dwyer) and Niall (Corcoran).
"Ross O'Carroll in particular was a serious leadership figure throughout the year.
"He was a huge influence both on and off the pitch and he was always the one who ensured the lads remained driven and focused on the task in hand and his role was crucial," insisted Mulligan.
With his club ambitions sated for now, despite the disappointment of a provincial exit at the hands of Oulart-the-Ballagh, Mulligan's focus will now turn to fulfilling his talents at university and intercounty level.
His performances will undoubtedly have impressed incoming Dublin U-21 manager Shay Boland and his development should ensure he plays a prominent role when the Dubs enter the fray in early summer.
"Hopefully, I'll be involved with the panel. I would say my main goal now is to be selected on the Dublin U-21 team and see where I go from there.
"I'm really looking forward to the year and playing some Fitzgibbon Cup with the college who have a serious talented panel so that will be a good experience for me."