Josh van der Flier's controversially-awarded try helped Leinster to grind out a 13-0 Guinness PRO12 win over Connacht at a wet and windy RDS Arena.
The young flanker's converted score on the hour mark was awarded by referee George Clancy and TMO Marshall Kilgore, despite no clear grounding of the ball on the replays, with Connacht captain John Muldoon appearing to hold him up.
But Leinster deserved their sixth league victory on the trot, with man-of-the-match Eoin Reddan, Devin Toner and lively replacement Sean O'Brien, making his 100th provincial appearance, driving them to a hard-earned result.
Jonny Sexton's penalty on the quarter hour mark was the only score of a bruising, rain-soaked first half, with Connacht digging deep to prevent wind-backed Leinster from crossing their line.
The westerners, second in the table before kick-off, struggled for accuracy in attack, though, and Van der Flier's effort, coupled with a 74th-minute penalty from replacement Ian Madigan, sealed the points for Leo Cullen's men.
With a strong wind behind them, Leinster forced a series of early penalties, but the white-shirted visitors doggedly defended three lineout mauls in quick succession.
The pressure had to tell eventually and following two further Connacht infringements, Sexton slotted a straightforward 14th-minute penalty from in front of the posts.
A threatening break from Garry Ringrose amounted to nothing as Craig Ronaldson brought him down and then gobbled up a loose ball, and Eoghan Masterson won a relieving ruck penalty after another Leinster maul was halted.
A turgid spell was broken up by a couple of sniping runs from Eoin Reddan, who started in place of Luke McGrath (foot infection), but Connacht's excellent number eight Masterson poached a ruck ball to release the pressure.
It was Leinster's turn to feel the heat close to half-time, Niyi Adeolokun racing up to almost score from a Tiernan O'Halloran grubber kick towards the right corner. Having initially failed to gather the greasy ball, Dave Kearney recovered well to tackle Adeolokun into touch.
Into the second period, Connacht survived a slick midfield surge from Ringrose, a knock-on spoiling Leinster's latest attack, and O'Halloran hoovered up at the end of a Rob Kearney-initiated kick chase.
However, Kearney's younger brother Dave soon sliced open the Connacht defence on the left, powering into the 22 to set up a prolonged attacking spell. After a series of pick and goes, Van der Flier was adjudged to have forced his way over, with Sexton converting.
Bundee Aki tried to inject some pace into the Connacht attack, but he lacked support and some questionable decisions by Clancy also thwarted their progress.
The influence of Toner and O'Brien up front kept Leinster on course and Madigan knocked over the clinching penalty with six minutes left, confirming the province's rise to second place - just a point behind the table-topping Scarlets, with a game in hand.