A MENTOR, a man who conquered all before him in gaelic football, but someone who still kept his modesty and was always available to offer advice - personal, sporting and professional - to those who sought it.
Taoiseach Enda Kenny described him as "one of the real legends of the GAA" who "revolutionised the way teams trained and the way the game was played".
A native of Marino on the capital's northside, Mr Heffernan played both hurling and football for St Vincent's as well as for Dublin.
He won 21 Dublin county championships, with 15 for a storied St Vincent's football side. Vincent's was his main passion, and he still coached underage teams in the Marino club until recently.
As corner forward, he captained Dublin to All-Ireland football success, beating Derry in the 1958 final. He also won four Leinster titles as a player with Dublin and was selected on the GAA's teams of the millennium and of the century.
Former Dublin goalkeeper Paddy Cullen, who played under Mr Heffernan in the 1970s, last night said his former manager was "gone to god, lining out at number 15".
He took over as Dublin football manager in 1973, achieving All-Ireland victory in 1974, his first full year in charge. Another followed in 1976, but he stood down as manager soon after, before returning in 1979.
The rivalry of the Dubs of Mr Heffernan's era and the Kerry team under Mick O'Dwyer has gone down as one of the most legendary in the GAA.
He rebuilt his side in the 1980s, and led them to another All-Ireland in 1983, when the 12 men of Dublin beat Galway's 14 after four players were sent off.
His teams are widely credited with turning around the fortunes of a declining GAA in the capital, attracting huge crowds of 'Heffo's Army' to Croke Park and Hill 16.
"When he asked me to play in 1973, Dublin football wasn't as attractive as it is now," Bernard Brogan Sr, whose sons are All-Ireland winners Alan and Bernard junior, said last night.
"We're a family steeped in the GAA, and a lot of that can be put down to Kevin Heffernan. Before that, I had no major family connection to the GAA."
The players of his famous teams of the '70s and '80s say he created an unshakeable bond that lasts to this day, with the team, Mr Heffernan and his selectors Lorcan Redmond and Donal Colfer meeting up once a year for golf.
"As a group, we wouldn't be here without him," said Alan Larkin, another player who lived near Mr Heffernan.
"A testament to him would be our close connection, which endured because we saw that it was something special he created.
"He is the first of our group to die, so he's still leading the way," said David Hickey, who also played in the '70s teams.
Former Dublin manager Pat Gilroy was a clubmate at St Vincent's, and described Mr Heffernan as a "modest man" who would "never impose himself on anyone".
"Around the club, if you came to him looking for advice he would always give it, whether it was with the under nine team or whatever."
Mickey Whelan played alongside Mr Heffernan and said he was an exceptional footballer. Mr Whelan said he was still asking after the Dublin footballers when visited by Shane O'Hanlon, a county selector, earlier this week.
"His fingerprints were on every success that Dublin have had since his time," Mr Whelan said.
"He was a goalsmith. He was great at reading the game and knowing what to do at different stages of a game.
"He was a great friend and mentor, he took me under his wing when I was just a 19-year-old playing for Dublin.
"You could go to him and ask him things and he would dissect the chaff from the wheat in a cool manner."
Kevin Heffernan is survived by his wife Mary, daughter, Orla and extended family.