Bench clinches an unlikely bonus for sleepy Leinster
Leinster 37 Cardiff Blues 9
It was an unforgettable evening for Devin Toner who led his side to victory in his 200th game, but a forgettable game for long stretches until a late scoring burst sealed the most unlikely of bonus points.
A James Tracy try had helped edge Leinster 10-6 ahead at the break but three tries in eight whirlwind minutes from replacements Sean Cronin, Barry Daly and Nick McCarthy guaranteed Leo Cullen's men a second successive maximum haul ahead of their South African trek.
Rob Kearney will not make the plane after failing to return for the second half, however.
Early shadow boxing between the mostly shadow sides was fairly uninspired.
An early Steven Shingler spill put his side under the cosh but Leinster, despite some early probing, lost a five-metre line-out and Ross Byrne skewed a penalty attempt off target.
From their first possession, Cardiff ran some decent ball, aided by poor shooting from Leinster defenders and when Jack Conan was pinged on the floor, Shingler kicked his side into a 15th-minute lead.
Cardiff then pinned Leinster back for long spells until Isa Nacewa's kick and chase threatened brief relief, until his flailing arm at the end of the chase, catching Alex Cuthbert with a wild hook, left the captain pondering his guilt in the bin.
In truth, it was all legs and arms and not much brains for the most part, from both sides. Shingler popped over a 28th-minute scrum penalty for 6-0 after Michael Bent lost his bind. Leinster were losing their way.
A Rory O'Loughlin burst, a Jordan Larmour shimmy and some fine carries from Jack Conan, in particular, helped them find it and soon, via a close-in drive, they had mauled their way over their whitewash, Tracy credited with the score via another trip to Peter Fitzgibbon in the TV truck.
A contrite Nacewa trundled back on as Byrne's conversion edged his side ahead six minutes before they were all due another break. Just on the whistle, Josh Navidi took out Nacewa as he chased a speculative Byrne chip; the out-half's penalty ended an undistinguished half with his side 10-6 up.
Kearney didn't return after shipping one of the half's many late body-checks. Shingler's early penalty then narrowed the margin to its minimum but Byrne responded, a la Tim Stimpson in Europe all those years ago, by banging over a three-pointer via both uprights.
Larmour's kick then sent replacement Daly scampering down the tram-line but sadly most of his body traversed it as he attempted to dot down in the corner.
Leinster were missing the invention and unpredictability of a Joey Carbery and Byrne was struggling in phased play.
Byrne managed the quirky feat of snapping an upright with another penalty effort; this time his luck ran out and the ball rebounded to the ongoing clutter of the loose play.
He seemed more at ease with a longer-range effort just on the hour and dutifully spanked one from 45 yards dead on in front to extend the lead to 16-9.
The game mercifully opened up and that suited Cronin; from the bench, he benefited from Scott Fardy's half-way line steal and completed the testing five-furlong spring to the line as only he can.
Daly soared wonderfully to touch down Byrne's lofted cross-kick in the 75th minute and suddenly the most unlikely of bonus points was there to be taken. McCarthy, another replacement, grabbed it, completing a fine team try from the restart.
Leinster - R Kearney (B Daly h-t); A Byrne, R O'Loughlin, I Nacewa (c), J Larmour; R Byrne, L McGrath (N McCarthy 72); C Healy (E Byrne 53), J Tracy (S Cronin 53) , M Bent (A Porter 53); D Toner, S Fardy (M Kearney 74); R Ruddock (D Leavy 58 (C Marsh 77), J van der Flier, J Conan.
Cardiff Blues - R Williams (M Morgan 72); A Cuthbert, G Smith, R Lee-Lo, T James; S Shingler (J Evans 71), L Williams (T Williams 71); R Gill (C Domachowski 57), M Rees (c) (K Myhill 61), K Assiratti (D Lewis 57); S Davies, D Welch (J Down 64); M Cook (S Bennett, 75), J Navidi, J Turnbull.
Ref - Andrew Brace (Ireland).