A 66th-minute try from centre Shane Horgan helped Leinster edge a low-scoring provincial derby at Musgrave Park as Michael Cheika’s men brushed aside the challenge of Munster to move to the top of the Magners League.

The quick feet and quick thinking of Luke Fitzgerald led to Horgan going over in the right corner at a crucial stage in this provincial derby. Horgan managed to hold off a tackle from Ian Dowling and aided by a shove from replacement Keith Gleeson, the big Drogheda man made the whitewash.

In a game of such importance and with the wicked weather conditions having more than an influence, that try was the telling blow as despite huffing and puffing right until the finish, Munster failed to hold onto their proud home record against their blue-shirted rivals.

Leinster had not won away in Munster since 1998 and you have to go back to November 1985 for Leinster’s last victory at Musgrave Park.

Another plus point for Michael Cheika and his management team is that Leinster have won away from home against Cardiff Blues, the side they replaced at the summit, the Ospreys and Munster now and that string of results could prove crucial come May time.

In wet and windy conditions, the provinces took to the pitch with ten Ireland internationals each in their starting line-ups. Buoyed by last week’s seven-try triumph over Newport Gwent Dragons, Munster were looking for more of the same but they made a poor start when spilling the kick-off and infringing at the first scrum.

Felipe Contepomi, who was this week crowned the Rugby Writers of Ireland’s Player of the Year, did the necessary for Leinster and kicked them into a first-minute lead.

Both sides peppered the night sky with high balls as they tried to force one another into mistakes but in full-back and team manager Shaun Payne Munster have one of the best fielders in the game.

Payne hardly put a foot wrong in the first half while, given the tricky underfoot conditions, Leinster’s Rob Kearney was also an assured presence at full-back.

Ronan O’Gara missed a sixth-minute penalty chance to level but redeemed himself in the 13th-minute when he raised the touch judges’ flags with an excellent effort from just inside the Leinster half.

3-3 is how it stayed until the 66th-minute and Horgan’s try, but Leinster did miss two gilt-edged opportunities in the opening half.

The Leinster pack, bulked up from last week by the inclusions of Bernard Jackman, Leo Cullen and Jamie Heaslip, put in a magnificent effort all night and succeeded in outplaying the hosts’ eight for much of this encounter.

On one such occasion, 20 minutes in, they made it up close to the Munster try line. A try looked on the cards but Leinster lost their patience and Munster seized back control thanks to some disciplined defence.

Having lost Chris Whitaker and Girvan Dempsey to injury in recent weeks, Leinster were hit with another blow on the half-hour mark when their talismanic captain Brian O’Driscoll had to hobble off with an ankle injury.

Jonathan Sexton, the young fly-half, was sprung from the visitors’ bench and he took over at number 10 with Contepomi joining Gordon D’Arcy at centre.

The Leinster front eight continued to look the more cohesive unit and another maul, close to half-time, had them within sight of the whitewash. Frustratingly for their vocal band of supporters, the ball was turned over after Gordon D’Arcy had made decent ground.

Those try-scoring chances must have been swirling around in the Leinster players’ minds at half-time and predictably, Munster came out for the second half and sought to take the game by the scruff of the neck.

They did have the possession to do so but many facets of their game were not up to the usual high standard and with O’Gara missing three penalty kicks out of four attempts on the night, the home support had little to cheer.

Between two O’Gara missed after 45 and 64 minutes, Contepomi also sent an effort wide of the uprights before Fitzgerald’s terrific break on the right put Horgan into space and over for a try which television match official Brian Fitzgerald confirmed.

Contepomi rubbed salt into Munster’s wounds by landing the difficult conversion kick for a 10-3 lead and Leinster doggedly held on for a famous win.