Munster took a giant step towards winning the Magners League title as they clinically despatched their arch-rivals Leinster in front of a capacity Thomond Park crowd.

Second-half tries from Keith Earls and Denis Fogarty helped the European champions storm to a deserved victory but this so-called 'Battle of Ireland' really was definitely a tale of two number 10s.

Leinster's Felipe Contepomi, who is leaving for Toulon in the summer, had a nightmare outing, missing four kicks at goal (11 points) and struggling throughout to direct his team's attacks.

In contrast, Munster playmaker Ronan O'Gara marshalled his side superbly and his 12-point kicking contribution laid the foundations for a win which has Tony McGahan's men seven points clear at the league's summit.

Leinster were missing the injured Brian O'Driscoll (neck), Luke Fitzgerald (shoulder) and CJ Van Der Linde (toe) but were clearly determined to gain revenge for September's 18-0 defeat to Munster at the RDS.

Munster started with a Grand Slam-winning front five but the Leinster scrum more than held their own, with young pretender Cian Healy edging his battle with Ireland's most-capped player John Hayes.

In dry, cool conditions, the anticipated frantic start was full of crunching tackles and full-blooded attacking.

Leinster eked out the first scoring chance but the off-colour Contepomi screwed his third-minute penalty wide.

Girvan Dempsey and Shane Horgan, two forgotten men in Ireland's Grand Slam triumph, looked lively in attack but Munster's experienced hands soaked up the early pressure.

The cat-and-mouse opening quarter ended with Rocky Elsom, Healy and Horgan making serious ground for the visitors, but frustratingly for the travelling support they remained scoreless.

Munster used their forward guile - with Alan Quinlan very effective at the breakdown and in broken play - and their speed out wide to gain crucial territory.

Doug Howlett threatened twice before O'Gara kicked two penalties in the space of six minutes to move Munster ahead on the scoreboard.

Referee Christophe Berdos drew boos from the home crowd when failed to play an advantage for Munster as Ian Dowling charged down the left, but a 6-0 interval lead was a fair score on the balance of play.

Rob Kearney mishit a long range penalty attempt in first half injury-time and with nothing to show for their first half efforts, Leinster had plenty to do.

On the restart, Munster drew a penalty at a breakdown and O'Gara landed the resulting kick to add to Leinster's growing frustration.

Wallaby star Elsom carried the fight, as he has done for much of the campaign, but too few of his team-mates were stepping up to the mark and Munster's clinical edge quickly saw them forage ahead.

O'Gara was at the heart of it, as he followed up on his own sublime touch-finding kick to drop a masterful goal after Paul O'Connell produced a lineout steal.

With Contepomi missing his second and third penalty attempts, Munster effectively moved out of sight on 62 minutes when Earls danced along the left touchline and muscled over in the corner past Kearney.

David Wallace freed up Earls with an excellent offload out of the tackle and the Limerick-born centre handed off Healy before making the line before Kearney's last-gasp challenge.

O'Gara missed the conversion and Horgan, combining well on the loop with Isa Nacewa, sent Gordon D'Arcy through for a well-taken try as Leinster showed signs of a revival.

But Contepomi failed to add the extras and although Munster lost Lifeimi Mafi to the sin-bin late on - for tangling with Jonathan Sexton - they rubbed salt into Leinster wounds when O'Gara unleashed Barry Murphy down the left and his well-timed pass sent Fogarty over for the crowning score.