Leinster 24 Ulster 10
Leinster moved into fourth place in the Guinness PRO12 with a huge second half display which saw them deserved winners in front of a sell-out RDS Arena in Dublin.
Ulster had dominated the first half, but once again failure to take chances and some ill discipline saw them trail 9-6 at the break.
The victory was just the tonic Leinster needed after an indifferent run of form recently, including losing to Munster for the second time this season a week ago.
For Ulster, the search to find form on the road this season will continue next weekend when they play a Benetton Treviso side in Italy buoyed by two straight PRO12 wins.
Good phase of pressure from Ulster, several phases backs and forwards, but Fergus McFadden ripped possession from Ulster lock Dan Tuohy to halt the charge close to the line after nine minutes.
Having weathered some Leinster pressure a big hit by Tuohy on Jack McGrath led to a penalty on half way, scrumhalf Ruan Pienaar saw his effort come off the crossbar on 13 minutes. Three minutes later he had a second - after Ian Madigan’s high tackle on Stuart Olding - a few yards inside the Leinster half and nailed it for a 3-0 lead.
However, two poor penalty giveaways from Ulster in Leinster’s first real serious attack and it was 3-3 through outhalf Madigan.
Ulster nudged ahead again after another brave take by Peter Nelson in the air led to another series of punching runs by forwards and backs, Pienaar making it 6-3 on 26 minutes.
Leinster lost captain, Jamie Heaslip after 28 minutes replaced by Josh van der Flier and he was instrumental in the home attack which led to the equalising penalty chance for Madigan on 31 minutes.
Leinster were to take an unlikely 9-6 lead into the break after a soft penalty giveaway by Ulster, Dan Tuohy also yellow carded and the last play of the front 40 saw Madigan send the Blues in at the break in front.
As expected Leinster put the squeeze on 14-man Ulster at the start of the second half, but the try which came three minutes after the restart was quite unexpected.
Opting for a penalty to touch, Madigan took tap-ball and backed himself to squeeze past Callum Black and Roger Wilson on the line. He then converted for a 16-6 lead.
Ulster then took advantage of a knockon by Issac Boss at a lineout and went for the try. A penalty had been awarded but advantage was played and Franco van der Merwe helped fellow South African Wiehahn Herbst over the line - confirmed by the TMO. Pienaar missed the conversion just as Tuohy returned to bring Ulster up to 15 players again.
Leinster began to dominate however and a break by replacement van der Flier almost led to a try, but Olding made a great tackle.
Ulster had to fire all into defence to halt a blue sea, but they did and they opted to kick a penalty for offside, Madigan making it five from five for a 19-11 advantage.
Pienaar missed a mid range effort for Ulster on 62 minutes and Leinster prop, Jack McGrath should have seen a yellow card at least for stamping all over Rory Best’s ankles, but he got away with a ticking off instead.
Madigan’s impressive kick to touch on 71 minutes kept Ulster on the backfoot as they had been for much of the second half.
Another bit of cheekiness from Madigan at another penalty option, but replacement Jimmy Gopperth knocked the ball on from the sort of crossfield attempt.
However, Leinster were not to be denied one final score, man of the match Jack Conan crashing over for a try. Madigan missed his only kick of the afternoon when the conversion went wide.
Leinster: Z Kirchner, F McFadden, L Fitzgerald, G D’Arcy, D Kearney, I Madigan, I Boss; J McGrath, R Strauss, M Ross, D Toner, M McCarthy, J Conan, J Murphy, J Heaslip (capt).
Replacements: S Cronin (Strauss 56), M Bent (McGrath 71), T Furlong (Ross 56), K Douglas (McCarthy 61), J van der Flier (Heaslip 28), L McGrath (Boss 68), J Gopperth (Kirchner 74), B Te’o (D’Arcy 76).
Ulster: P Nelson; T Bowe, D Cave, S Olding, C Gilroy, P Jackson, R Pienaar; C Black, R Best (capt), W Herbst, D Tuohy, F van der Merwe, R Diack, C Ross, R Wilson.
Replacements: R Herring (Best 74), A Warwick (Black 68), B Ross (Herbst 68), A O’Connor (van der Merwe 68), S Reidy (C Ross 63), P Marshall (Pienaar 74), I Humphreys, L Marshall (Bowe 48).