Four penalties from Isa Nacewa helped Leinster come from behind and record a hard-fought 30-20 victory over local rivals Connacht.
After a tight first quarter, in which Connacht edged into a 6-3 lead despite having prop Dylan Rogers sinbinned, Leinster grabbed the opening try of the game through towering lock Devin Toner.
After being restored to their full complement though, Connacht worked their way back into the game and scored an excellent try in the 31st minute through number eight Ray Ofisa Treviranus after a looping pass from fly-half Niall O'Connor, who also added the conversion.
Connacht's backs continued to show their ability in the final ten minutes of the first half and were rewarded when winger Brian Tuohy finished off a good move to give them a commanding 20-8 lead at the break.
However, two penalties from the boot of Fijian full-back Isa Nacewa early in the second half put Leinster back in contention before promising fly-half Ian Madigan cut Connacht's lead to just three points with a long-range shot at goal.
With pressure building Luke Fitzgerald then crossed under the posts in the 65th minute, giving Nacewa an easy conversion attempt and meaning Leinster lead for the first time since the opening half hour.
Nacewa slotted another penalty with five minutes remaining to give Leinster a bit more breathing space before Madigan sent over a drop goal in the final seconds to deny Connacht a losing bonus point.
Tries: Toner, Fitzgerald
Pens: Nacewa 4, Madigan
Tries: Ofisa, Tuohy
Cons: O'Connor 2
Pens: O'Connor 2
Leinster: 15 Isa Nacewa, 14 Fionn Carr, 13 Eoin O'Malley, 12 Luke Fitzgerald, 11 Dave Kearney, 10 Ian Madigan, 9 Cillian Willis, 8 Leo Auva'a, 7 Rhys Ruddock (c), 6 Kevin McLaughlin, 5 Devin Toner, 4 Steven Sykes, 3 Jamie Hagan, 2 Richardt Strauss, 1 Heinke van der Merwe.
Replacements: 16 Jason Harris-Wright, 17 Jack McGrath, 18 Jack O'Connell, 19 Damian Browne, 20 Jordi Murphy, 21 John Cooney, 22 Brendan Macken, 23 Darren Hudson.
Connacht: 15 Gavin Duffy (C), 14 Mark McCrea, 13 Eoin Griffin, 12 Henry Fa'afili, 11 Brian Tuohy, 10 Niall O'Connor, 9 Frank Murphy, 8 Ray Ofisa, 7 Johnny O'Connor, 6 John Muldoon, 5 Mike McCarthy, 4 Michael Swift, 3 Dylan Rogers, 2 Adrian Flavin, 1 Brett Wilkinson.
Replacements: 16 Ethienne Reynecke. 17 Ronan Loughney. 18 Rodney Ah You. 19 Dave Gannon. 20 TJ Anderson. 21 Paul O'Donohoe. 22 Matthew Jarvis. 23 Dave McSharry
Venue: RDS, Dublin
Referee: Peter Fitzgibbon
Assistant Referees: John Lacey, Mark Patton
TMO: Dermot Moloney