Leinster were forced to come from behind via two penalty tries to beat Dragons 31-19 in Friday's PRO12 clash at the RDS in Dublin.
The hard-fought, bonus-point win, moves Leinster top of the standings.
Dragons led early in the second half after scoring two tries in quick succession, but the award of two penalty tries swung the momentum back the way of the home side and prevented the much-fancied Irish province falling to a shock home defeat.
A tight first-half saw Leinster take 13 minutes to get their first points on the board, fly-half Ian Madigan kicking his first attempt at goal from 35 metres out.
Resolute defending from the Dragons meant the scoreline stayed the same until the visitors were rewarded for their best passage of play through the boot of Jason Tovey.
After 14 phases of play inside the Leinster half, fly-half Tovey decided enough was enough and dropped back into the pocket to strike a well-taken drop goal with his left foot.
Dragons then lost tighthead prop Nathan Buck to a yellow card and fellow forwards Nic Cudd and Netani Talei to injury in quick succession, and eventually Leinster took advantage by scoring the first try of the evening three minutes before the break.
Prop Jack McGrath broke through Rob Sidoli's attempted tackle and carried two defenders with him over the line to bring some much needed cheer to the RDS crowd. Madigan added the extras to hand the Irish province a 10-3 lead.
However Dragons hit the ground running at the start of the second half, scoring two tries within the space of three minutes.
Turnover ball saw Dragons spread the ball out wide to Matthew Pewtner and after being hauled down just short of the line the winger popped the ball up to centre Ashley Smith to score.
Scrum-half Richie Rees crossed for the Dragons' second try two minutes later, and while Tovey was unable to convert either score he did kick a penalty to put the Welsh side 16-10 up with less than half an hour to go.
The game turned Leinster's way when replacement forward Jevon Groves was yellow-carded for collapsing a maul close to the line.
Leinster took the scrum option and marched the opposition backwards to give Italian referee Marius Mitrea no option but to award a penalty try.
He repeated the act seven minutes later as Leinster extended their lead to 24-16 before Tovey slotted a late penalty to bring Dragons back within losing bonus point territory.
However all their hard work was undone when replacement Nahuel Tetaz Chaparro was sent off late on and Leinster capitalised to secure the bonus point through Darren Hudson.
Tries: McGrath, Penalty try 2, Hudson
Cons: Madigan 4
Tries: Smith, Rees
Pens: Tovey 2
Yellow cards: Buck, Groves
Red card: Chaparro
Leinster: 15 Zane Kirchner, 14 Fergus McFadden, 13 Brendan Macken, 12 Noel Reid, 11 Darragh Fanning, 10 Ian Madigan, 9 Eoin Reddan, 8 Jordi Murphy, 7 Shane Jennings, 6 Rhys Ruddock, 5 Mike McCarthy, 4 Leo Cullen (c), 3 Martin Moore, 2 Sean Cronin, 1 Jack McGrath.
Replacements: 16 Aaron Dundon, 17 Michael Bent, 18 Tadhg Furlong, 19 Tom Denton, 20 Dominic Ryan, 21 Issac Boss, 22 Jimmy Gopperth, 23 Darren Hudson.
Dragons: 15 Hallam Amos, 14 Matthew Pewtner, 13 Pat Leach, 12 Ashley Smith, 11 Will Harries, 10 Jason Tovey, 9 Richie Rees, 9 Netani Talei, 7 Nic Cudd, 6 Lewis Evans, 5 Rob Sidoli (c), 4 Cory Hill, 3 Nathan Buck, 2 T.Rhys Thomas, 1 Owen Evans.
Replacements: 16 Sam Parry, 17 Aaron Coundley, 18 Francisco Chaparro, 19 Matthew Screech, 20 Jevon Groves, 21 Wayne Evans, 22 Steffan Jones, 23 Ross Wardle.
Referee: Marius Mitrea (Italy)
Assistant Referees: Marc Patton (Ireland), Barrie O'Connell (Ireland)
TMO: Kevin Beggs (Ireland)