Leinster had to be consoled by a single bonus point when they lost (25-19) in the PRO12 League for the first time since December to the Ospreys at The Liberty Stadium last night.
Initially, Leinster took control of the ball, with Jamie Heaslip and Shane Jennings to the fore for Jimmy Gopperth to strike in the 10th minute, Dan Biggar reversing the trend from penalties in the 16th and the 21st minutes.
When Gopperth was deemed to have taken Tom Habberfield in the air, the Ospreys had momentum again, Biggar missing with a straight forward drop goal from close in.
The home side almost made the breakthrough when the quick hands of Biggar created space wide on the right for Jeff Hassler, only for Rob Kearney to arrive in time.
It delayed the inevitable as Hassler countered with intent from a stray clearance by Isaac Boss for full-back Richard Fussell's flick to feed onrushing wing Hassler for their only try of the evening. Biggar converted for a 10-point lead.
Leinster needed something quickly or risk having the game drift away from them. Zane Kirchner did well at the restart. Martin Moore did even better on the ball.
They were awarded a penalty. Gopperth could have gone for the posts. Rob Kearney went for the corner. Prop Cian Healy carried the ball at the back of a maul for a textbook try, converted by Gopperth, for 13-10 at the interval.
Referee Marius Mitrea harshly whistled Healy for coming in at the side of a ruck in the 43rd minute and Shane Jennings for not rolling away at another for Biggar to make it 19-10 in the 52nd minute.
Healy really started to hit his straps off the shoulder of Jamie Heaslip, even tidying up a scrappy pass before Gopperth struck for three points to stop the rot in the third quarter.
Gopperth's superb pass almost put Dave Kearney into the left corner. Heaslip stole a ball on the floor. The Ospreys killed it at ruck time and the New Zealander split the sticks.
The fly-half was back for his fifth kick in six attempts to bring Leinster back on terms when Justin Tipuric was penalised for not releasing replacement Mike McCarthy in the tackle.
The Ospreys stemmed the tide when Biggar popped up for a snap drop goal to recover their lead. Dave Kearney threatened down the left flank; Shane Jennings down the right.
It all came to no avail as Biggar smacked over the final points in the 77th minute.