Leinster 0 Munster 18: Given their current predicaments and their opposition this weekend it was of little surprise that Connacht and Ulster drew blanks, but few would have anticipated that the Magners League title holders would be held scoreless on their home patch, even if they were renewing hostilities with their fierce rivals - the European champions.
It will be of scant consolation to the Leinster fans but they can be sure that there team left nothing on the pitch.
It was ferocious and frantic. And it was completely absorbing. As is so often the case, the two sides cancelled each other out for much of the game, but as the hits continued, the team doing most of the defending was always likely to crack in the end.
And so it was for Leinster. They put everything on the line to stop Munster from crossing theirs before being undone by a South African and a Kiwi in the closing stages.
Three-month loan signing Justin Melck was first to crash over after a brilliant break and offload from Keith Earls, before Ronan O'Gara's perfect grubber kick under the posts was expertly collected and grounded by Doug Howlett for the first win over Leinster by an Irish province at the RDS in five years.
The result wasn't quite enough to send Tony McGahan's side back to the top of the table but after four wins out of four and with a game in hand on leaders Ospreys, few will be concerned about that.
Not that it was all about Munster. The only thing Leinster did not contribute to was the scoreboard.
They got the opportunity on three occasions early on but Felipe Contepomi uncharacteristically missed each penalty, two of which he would usually put over with his eyes closed.
In defence, his indiscipline afforded O'Gara a sight of the posts and the Ireland outhalf wasn't as wasteful.
Munster made much of the running from then to the break with O'Gara superbly keeping the pressure on with some sublime line-kicking, but there was to be no more points as Leister refused to budge, as the hits, from debutants CJ van der Linde and Rocky Elsom in particular, flew in.
Even Paul O'Connell was diverted over the touchline by Jamie Heaslip when he looked too close to stop.
Despite losing hooker Jerry Flannery to a shoulder injury Munster brilliantly ground their way into a winning position in an attritional second period.
O'Gara tapped over a second penalty close to the hour mark and with replacement Alan Quinlan causing headaches at the breakdown, Leinster grew frustrated.
Munster's sheer work-rate drove them on and when Earls burst down the left wing, the hosts defence was badly exposed.
The youngster was tackled but passed inside from the ground to number eight Melck who made the line as Rob Kearney paid too much attention to Lifeimi Mafi who was in support.
It was the game's turning point and Leinster never recovered.
O'Gara completed a masterful performance when he anticipated Howlett's run from deep but the New Zealander still had work to do. Thankfully for Munster, the TMO confirmed he did it well.
