That match winning score came at a stage when Munster led 13-10 thanks to a 70th minute Jeremy Manning penalty but replacement lock Alex Dunlop got on the end of a rolling maul to crash over the Munster line in stoppage time for the decisive try. And just for good measure, Eoghan Hickey, landed the difficult conversion from wide on the right into a swirling wind.
On balance it was a victory Leinster scarcely deserved because for most of the game they were forced to play from inside their own half as Munster varied their attack using backs and forward to establish field position in Leinster territory.
Leinster did open brightly and on their first incursion into the Munster 22 scored the opening try when Christian Warner off-loaded superbly in the tackle to set John Hearty away.
However, for the remainder of the half Munster dominated territorially and with a little more patience mght have establihd a commanding lead. They tied matters in the 25th minute when out-half Conan Doyle carved open the Leinster defence and released winger Richie Lane down the middle of the park.
The former Under 21 international was collared on half way but his well-timed pass found Martin McPhail and the Ireland Sevens star raced over to level the scores.
David McAllister really should have sent his into the break in the lead but his penalty from 25 metres flew wide of the left upright.
Munster went in front 10 minutes after the restart when Brian Touhy collected replacement Mike Kingsbear s clever kick ahead to score on the right but the sides were level once again at the start of the final quarter when the impressive Jamie Heaslip gained full return from a driven five metre scrum.
With just ten minutes remaining Manning edged Munster in front but Leinster refused to buckle and Dunlop s late score came when the Leinster pack drove over from a five metre line-out
Munster: D Hurley; R Lane (P Hurley 50 min), T Gleeson (M Kingsbear ht), M McPhail (B O Donnell ht), B Tuohy (D Corcoran 74 min); C Doyle (J Manning ht), F Murphy ( M Prendergast 60 min); R Callaghan (M Storey 60 min), F Roche (N Conroy 70 min), E McGovern; D Pusey, S O Connor (R Noonan 62 min); F Cogan (R Hartigan 72 min), J O Connor (M Essex 70 min), T Hayes
Leinster: C Warner; J Norton, J Hearty, E Hickey, R McCarran (M Hastings ht); D McAllister (R Kearney 55 min), B O Riordan; P Coyle, C Geoghegan (B Blaney ht), N Treston (A O Donnell ht (A O Sullivan 62 min); D Gannon, C Kos (A Dunlop 60 min); S Crawford, Dave O Brien (K Croke 60 min), J Heaslip.
Referee: G Clancy (MAR).