LEINSTER (20) 30
- Tries: Strauss, Madigan, O'Driscoll
- Cons: Sexton 3
- Pens: Sexton 3
MUNSTER (14) 21
- Tries: O'Mahony, Murray
- Con: Keatley
- Pens: O'Gara 3
Leinster overcame a resilient Munster in the Pro12 derby clash to give themselves a timely boost before the launch of their Heineken Cup defence.
Richard Strauss scored an early try for the hosts but Munster hit back with Peter O'Mahony's try before Ian Madigan went over to edge Leinster ahead.
Leinster held a 20-14 lead at the break and Brian O'Driscoll added their third try to extend the advantage.
Conor Murray's try gave Munster hope but Leinster held firm for the win.
Leinster were on the scoreboard after four minutes - from a a five-metre scrum they sprung to the left and Strauss was able to spin out of Donnacha Ryan's tackle to score under the posts, with Jonathan Sexton converting.
But Munster's rapid response would have warmed the heart of new head coach Rob Penney.
Keith Earls roared up the right wing and numbers on the left created the space for O'Mahony to reach over in the corner, although Ronan O'Gara was unable to convert.
The scores kept coming as O'Gara sandwiched a Sexton penalty with two of his own, giving Munster an 11-10 lead heading into the second quarter.
Sexton had struck the left-hand post with his second effort as Munster began to leak successive penalties, and Leinster soon regained the lead.
They pressed through the middle, man of the match Eoin Reddan delivering some deft passes, before Madigan stepped inside Casey Laulala's challenge to slip through for a neatly-taken 21st-minute try.
Sexton converted to move the European champions 17-11 clear, the added cohesion brought by O'Driscoll and company having a telling effect.
Increasing pressure on the Munster scrum gave Sexton two more shots at the posts, the second of which he landed to punish David Kilcoyne for bringing the set-piece down.
Strauss infringed at a central ruck moments later, allowing O'Gara to boot the visitors back to within a converted score on the cusp of half-time.
The woodwork denied O'Gara early in the second period as he suffered his first penalty miss of the night.
A sumptuous strike from Sexton then kick-started a key spell from the hosts.
The direct running of Fergus McFadden and Strauss parted the Munster defence and O'Driscoll somehow scrambled his way over in the left corner.
The Ireland captain dotted down with his outstretched left arm despite the presence of Denis Hurley and the late-arriving Simon Zebo.
It was a real hammer blow to Munster's chances and Damien Varley, barely on the pitch, was immediately yellow-carded by referee Leighton Hodges as he paid the price for his side's repeated ruck infringements.
The conversion was added by Sexton, his sixth success from eight kicks, and Munster had a mountain to climb.
But as Leinster lost Isa Nacewa, O'Driscoll and Andrew Conway to injury, Munster pulled back a try as Murray lunged over unopposed following a pack drive.
O'Gara's replacement Ian Keatley weighed in with a tremendous touchline conversion to bring it back to a nine-point deficit and suddenly it was game on again.
The Munster forwards looked re-energised, with their scrum making inroads, and Laulala was denied a try by a marginal knock-on call.
Both sides pushed for a late bonus point with John Cooney and Earls leading breaks, but the scores dried up as Leinster were left to celebrate an eighth win in their last 10 meetings with Munster.
I Madigan; A Conway, B O'Driscoll, F McFadden, I Nacewa; J Sexton, E Reddan; H van der Merwe, R Strauss, M Ross; D Browne; K McLaughlin, S Jennings, J Heaslip (capt).
J Cooney for Conway 65, N Reid for O'Driscoll 64, F Carr for Nacewa 52, S Cronin for Strauss 57, J Hagan for Ross 65, T Denton for Browne 72, J Murphy for McLaughlin 13
Not used: J McGrath
D Hurley; D Howlett (capt), K Earls, C Laulala, S Zebo; R O'Gara, C Murray; D Kilcoyne, M Sherry, BJ Botha; D O'Callaghan, D Ryan; Dave O'Callaghan, S Dougall, P O'Mahony.
J Downey for Zebo 65, I Keatley for O'Gara 61, D Varley for Sherry 51, B Holland for Dave O'Callaghan 46, P Butler for Donncha O'Callaghan 69.
Not used: W du Preez, S Archer, D Williams