Jimmy Gopperth kicked 11 points as Leinster battled to a 21-11 win over Connacht in Dublin.
A first half try from Shane Jennings gave Leinster the lead, though the visitors hit back before the break with two penalties to close the lead to two points.
A late Devin Toner yellow card was followed by a try from George Naoupu to ensure a nervy ending.
But Leinster sealed the victory with a Zane Kirchner try minutes from time to take Leinster joint top.
Leinster went close early on, though Luke Fitzgerald was held up inches short of the try line, in a fairly even opening period.
Connacht were dealt an early blow, with Aly Muldowney yellow carded 11 minutes in following a foul at the line out.
And Leinster made their visitors pay for that four minutes into the advantage. Following a line-out, Jennings made his way over the line after a strong drive towards the try area. Gopperth couldn’t get the resultant conversion however, hitting wide.
The lead was stretched to eight as Gopperth hit a penalty through the posts, and Muldowney returned to the field with his team behind.
Jack Carty fired a penalty narrowly wide for Connacht with his first effort of the evening, whilst Matt Healy pulled out a try saving tackle as he held up Kirchner as he bore down on the line.
Carty got his side’s first points of the night with a penalty, before they thought they had equalled.
Carty’s wonderful crossfield ball unleashed Danie Poolman, and he snuck over in the corner.
However, the TMO ruled he had stepped out of play as he went over, and Leinster’s lead was saved. But on the brink of half-time, Tadhg Furlong ensured he’d miss the first ten minutes of the second half, as he became the second victim of the yellow card. Carty’s resultant penalty saw the sides go in 8-6.
Gopperth’s penalty after the break saw Leinster extend their lead, even further when he fired three more points ten minutes later.
Connacht improved in the second half, and fell just short following a five-metre scrum, as they knocked on when it looked like their second try was imminent.
The game wore on with few clear cut opportunities, but it opened up nine minutes from time, following a yellow card for Toner.
Toner’s yellow sparked a nervy few minutes, especially so when Naoupu got a try that put the visitors within three points. Carty missed his kick however, and Leinster steadied the nerves with a try of their own five minutes from time.
Kirchner got the try, as he capitalised on Connacht’s inability to collect the ball following a kick towards touch. Gopperth finished the scoring, as Leinster moved to second spot, level on points with the leaders Munster.
Tries: Jennings, Kirchner
Pens: Gopperth 3
Yellow Cards: Furlong, Toner
Pens: Carty 2
Yellow Card: Muldowney
Leinster: 15 Rob Kearney, 14 Zane Kirchner, 13 Luke Fitzgerald, 12 Noel Reid, 11 Dave Kearney, 10 Jimmy Gopperth, 9 Isaac Boss, 8 Jamie Heaslip (c), 7 Shane Jennings, 6 Kevin McLaughlin, 5 Kane Douglas, 4 Devin Toner, 3 Tadhg Furlong, 2 Aaron Dundon, 1 Michael Bent
Replacements: 16 Sean Cronin, 17 Jack McGrath, 18 Maks Van Dyk, 19 Jack Conan, 20 Jordi Murphy, 21 Luke McGrath, 22 Cathal Marsh, 23 Gordon D’Arcy
Connacht: 15 Mils Muliaina, 14 Danie Poolman, 13 Robbie Henshaw, 12 Bundee Aki, 11 Matt Healy, 10 Jack Carty, 9 Kieran Marmion, 8 George Naoupu, 7 Eoin McKeon, 6 John Muldoon (c), 5 Aly Muldowney, 4 Quinn Roux, 3 Rodney Ah You, 2 Tom McCartney, 1 Denis Buckley
Replacements: 16 Dave Heffernan, 17 Ronan Loughney, 18 Finlay Bealham, 19 Ultan Dillane, 20 Willie Faloon, 21 Caolin Blade, 22 Craig Ronaldson, 23 Darragh Leader
Venue: RDS, Dublin
Referee: Ian Davies (WRU)