His goal changed the 2011 All-Ireland final in Dublin's favour and his goal was crucial in separating two outstanding football teams in one of the greatest games of all time.
The first half was a joy to behold with both sides throwing off the shackles and illustrating the undoubted talent both sides possess.
Kerry hit the onion sack three time in the opening period with Colm Cooper and James O'Donoghue purring but the Dubs still only trailed by two at the break.
The Dubs edged back into the game gradually in the second half but it was tit-for-tat until McManamon's heroics ensured they would take on Mayo in the All-Ireland final on September 22.
Jack McCaffrey's blistering pace set up Michael Daragh Macauley for the games opening point but that was quickly cancelled out by Declan O'Sullivan.
Bernard Brogan, who was scoreless from play in the quarter-final win over Cork, turned sharply and pointed before Diarmuid Connolly dissected the uprights.
Kerry struck for a goal in the seventh minute when Donncha Walsh's beautiful reverse pass found James O'Donoghue who found the corner of the net.
Dublin almost responded in perfect fashion but Brogan flashed wide when released by Paul Mannion.
A sumptuous point from James O'Donoghue was followed by a second Kerry goal as sublime vision from Colm Cooper saw him pick our Donncha Walsh who slif the ball past Stephen Cluxton.
Dublin this time responded in the best possible fashion as Paul Mannion expertly flicked a tame Diarmuid Connolly point attempt to the back of the net.
A Cluxton free and a brace from Bernard Brogan saw the lead change hands as Dublin led by 1-6 to 2-2 aftre 16 minutes.
Colm Cooper equalised with a typically cool point before Kerry were awarded a penalty after Stephen Cluxton hauled down Donncha Walsh and O'donoghue converted it with aplomb.
Dublin substitute Pilly McMahon kicked a fortuious point that bounced over before Cian O'Sullivan and the Gooch swapped points to make it 3-4 to 1-8 after 22 minutes.
James O'Donoghue was wreaking havoc and kicked Kerry into a three-point lead.
Ciaran Kilkenny, who was anonymous in the first half hour, pulled a score back for the Dubs and they trailed by 3-5 to 1-9 at the interval.
Paul Galvin and Bernard Brogan traded points in the opening five minutes of the second half with thesecond half lull that has plagued Kerry this year failing to materialise.
Points from the Gooch and another from Galvin stretched the Kingdom's advantage to four by the 43rd minute but Dean Rock, who replaced Kilkenny, responded by pointing with his first contribution.
Bernard Brogan fluffed a decent goal chance but scored a free soon afterwards to make up for that tame effort.
Paddy Andrews and Bernard Brogan raised white flags to draw the match level for the fourth time.
Dublin's tails were up and Diarmuid Connolly put Jim Gavin's men in front for the first time since the fourth minute with 20 minutes remaining.
Kieran Donaghy was summoned from the bench and he came on for Paul Galvin.
Cooper drew Kerry level after he was fould by Jonny Cooper but Rock restored Dublin's lead with 11 minutes left on the clock.
O'Donoghue restored parity for the sixth occasion in the game before Darran O'Sullivan scored from an incredibly acute angle.
Diarmuid Connolly assumed the responsibility to kick a free with his left foot and slotted it to leave things level with just two minutes to go.
The game looked to be heading for a draw but Kevin McManamon's attempt at a point flew over the head of Brendan Kealy and into the net.
Diarmuid Connolly popped up with the insurance point on the stroke of full-time.
Anthony Maher was sent-off for a second yellow in injury time and Eoghan O'Gara added a late goal as Dublin ran out seven point winners.