Dublin star Philly McMahon has opened up on the moment a young supporter helped him to discover his "purpose in life".

The Ballymun man has often spoken about the importance he places in helping his community, as well as his late brother's drug addiction and the problems that ravage the north Dublin suburb he grew up in.

McMahon, 31, dedicated his life to Gaelic football, and has gone on to establish himself as one of the county's most decorated players ever. The corner-back has won an incredible six All-Irelands and also runs a successful chain of gyms and a health food company.  

Speaking to RTÉ Radio 1's Saturday Sport, McMahon detailed an encounter with a boy five years ago that completely changed his perspective on his on-the-field success.

"You get asked a lot, how do you stay grounded? How do you motivated? You've won four in a row. Putting a smile on people's faces is very important," he said.

"I was doing a talk in a Ballymun youth club in 2013. I had the Sam Maguire. I just wanted to grab a bit of lunch before I went down.

"As I was going into my house it was like a Batman sign - all the kids saw the cup and they all came running over asking for autographs. I went and had lunch, came back down and one of the kid's younger brothers came over and said, 'I didn't get my jersey signed'.

"So I was signing his jersey and he looked up at me and said, 'are you famous?' Before I could say yes or no he said, 'you must be, you're on telly all the time'. I said 'ah yeah I am'. Then he said, 'but you can't be famous because you're from Ballymun'.

"So we sat down on the path, me, him and the Sam Maguire for about ten minutes. I don't know what I gave the kid that day but hopefully I gave him something positive to think about.

"That was the day that I found I had a purpose in life, to try and help people through my platform in sport."