Man of the match Diarmuid Murtagh, who scored 10 points, guided Roscommon to a Cadburys All Ireland under 21 football semi-final win over Cork at Portlaoise.
With Murtagh outstanding Roscommon were 0-11 to 0-05 ahead at the end of an absorbing opening period.
After the restart Cork bagged goals from Mark Sugrue (33 mins) and Alan Cadogan (48 mins) which ensured it stayed fascinating.
But there was further drama as Ultan Harney and Dan MacEoin swapped goals as Cork amazingly drew level right on 60 minutes, but Murtagh nailed a free with the last kick of the game to book Roscommon's place in the decider.
With Murtagh and Donie Smith carrying a serious threat inside, Roscommon ruled vast chunks of a thrilling first half.
By the time the interval rolled around they were protecting a commanding six-point advantage that was fully merited.
Nigel Dineen's team had been accurate throughout an opening period that belonged to the classy Murtagh.
The promising corner-forward kicked four sweet efforts including three from play and Cork were agitated going in at the break.
It had started fairly promisingly for Cork, who had impressed early on and with MacEoin influential the Rebels led by 0-04 to 0-03 following nine breathless minutes.
With the football of a seriously high quality Roscommon were revelling, though, and Dineen's charges seized the initiative, reeling off seven points without reply.
Enda Smith (2), Murtagh (2), Ciaran Kilcline, Harney, and Ronan Daly all found the range as the Rossies scorched six clear.
MacEoin ended a 20 minute search for a Cork score, but that was quickly cancelled out by Murtagh as Roscommon led 0-11 to 0-05 at the break.
Cork narrowed the deficit when MacEoin split the uprights before Murtagh responded again as the match continued to be played at a furious speed.
A splendid goal from Sugrue and a point from Alan Cadogan suddenly wiped the deficit down to two and Roscommon were being put under pressure.
The Connacht standard bearers, though, then hit four quick points in a row as Murtagh was ice cool from frees.
Cork were gritty and a brilliant 48th minute Alan Cadogan major had the margin down to two points, 0-17 to 2-09.
Roscommon didn't wilt and Harney unleashed a piledriver which looked to have sealed the deal with eight minutes remaining.
Cork, though, were wonderfully defiant as they hit 1-3 in a row including a stoppage time goal from a 20-metre MacEoin free.
But then, with the last kick, Murtagh held his nerve and Roscommon claimed a victory at the end of a gripping game.
Roscommon will now play Dublin in the final on Saturday 3 May.
Roscommon: C Lavin; D Murray, S Mullooly, C Kenny; N McInerney, J McManus, R Daly (0-01); U Harney (1-01), T Corcoran (0-02, 1 '45', 1f); C Kilcline (0-01), M Healy (0-01), E Smith (0-02); D Murtagh (0-10, 7fs), M Nally, D Smith (0-01). Subs: J Earley for Healy (60 mins)
Cork: M Martin; J Davis, C Dorman, S Cronin; K Fulignati, S White, K Crowley; K O’Hanlon, I Maguire; M Sugrue (1-03), B O’Driscoll, S Kiely (0-01); D MacEoin (1-06, 1-03fs), J Corkery, A Cadogan (1-02). Subs: K Histon for Fulignati (26 mins), K Kavanagh for O’Hanlon (26 mins), S Ryan for Corkery (48 mins), K McIntyre for Kiely (60 mins)
Referee: A Nolan (Wicklow)