Leinster ran five tries past Racing Métro to score a convincing 38-22 victory in their opening Heineken Cup match in Dublin on Saturday.
Stylish Leinster outscored Racing by five tries to one as they hit the ground running in Pool Two.
Fergus McFadden delighted the raucous RDS crowd by tearing up the right wing for a last-minute try, putting the seal on a deserved victory for Joe Schmidt's men.
They stepped it up another few notches from last weekend's league win over Munster, with tries from man-of-the-match Sean O'Brien and Rob Kearney putting them 21-6 ahead at half-time.
Leinster added a third from Richard Strauss, before Albert Vulivuli hit back for the Top 14 leaders, adding to Jerome Fillol and Francois Steyn's kicking haul.
Seven points was as close as they got in the second half though, as further tries from stand-in captain Heaslip and McFadden chalked up the bonus point.
Racing's Heineken Cup debut started with a thunderous tackle by Sebastien Chabal on his opposite number Heaslip, but the cult French figure was soon served some of his own medicine by Isa Nacewa.
A clever break from Gordon D'Arcy saw Leinster, with a gusting wind behind them, get within scoring range. Nacewa - taking the kicks instead of Jonathan Sexton - stepped up to slot a sixth-minute penalty.
Strauss breathed a sigh of relief when his South African compatriot Steyn failed to punish him for a ruck offence. However, Racing's second penalty attempt was good - Fillol, their third choice out-half, found the target from 40 metres out.
Racing struggled to use their much vaunted scrum to any advantage. Two early engagements were called against Leinster, but they got the rub of the green in the 29th minute when O'Brien managed to force a penalty out of Chabal, at the back of the set-piece, and Nacewa made it 6-3.
Two minutes later, the Irish side were celebrating their first try. Racing were caught napping at the restart - a regular occurrence - and after surges from D'Arcy and Mike Ross, a quick recycle saw Eoin Reddan put O'Brien over to the left of the posts.
Nacewa converted and there was just another two-minute pause before a scintillating back-line move, ignited by a well-worked loop between Sexton and Brian O'Driscoll, teed up Kearney for a classic Leinster try.
Steyn and Nacewa traded penalties coming up to the break, and Racing, with the elements behind them, made a purposeful start to the second half. Fillol landed a penalty to follow up on good work by his forwards.
But Leinster were no going to let things slip and after Racing scrum-half Nicolas Durand was sin-binned for a ruck offence, quick feet from Luke Fitzgerald created an opening in the corner for hooker Strauss to grab his first Leinster try.
A 10-point burst got Pierre Berbizier's side back in the hunt. Steyn drove a penalty over from inside his half and Vulivuli sauntered through a midfield gap to score his try, with O'Driscoll pulling a hamstring as the Fijian went by.
Fillol added the extras to set up an exciting final quarter, at the start of which runs from D'Arcy and replacements Cian Healy and Isaac Boss paved the way for Heaslip to raid in behind the posts.
Nacewa's simple conversion was cancelled out by a Fillol penalty as Racing, sparked by Sereli Bobo and replacement Mirco Bergamasco, hunted for a late losing bonus point.
But instead they got a harsh lesson in Heineken Cup finishing when Leinster quickly turned defence into attack, and McFadden took a pass from fellow replacement Shane Horgan to burn off Julien Saubade on a 60-metre dash to the line.
Tries: O'Brien, Kearney, Strauss, Heaslip, McFadden
Cons: Nacewa 2
Pens: Nacewa 3
For Racing Métro:
Pens: Fillol 3, Steyn 2
Yellow cards: Durand (Racing -44th min- deliberate off-side)
Leinster: 15 Rob Kearney, 14 Isa Nacewa, 13 Brian O'Driscoll, 12 Gordon D'Arcy, 11 Luke Fitzgerald, 10 Johnny Sexton, 9 Eoin Reddan, 8 Jamie Heaslip, 7 Shane Jennings, 6 Sean O'Brien, 5 Devin Toner, 4 Nathan Hines, 3 Mike Ross, 2 Richardt Strauss, 1 Heinke Van Der Merwe
Replacements: 16 Jason Harris-Wright, 17 Cian Healy, 18 Simon Shawe, 19 Mariano Galarza, 20 Dominic Ryan, 21 Isaac Boss, 22 Fergus McFadden, 23 Shane Horgan
Racing Métro 92: 15 François Steyn, 14 Sereli Bobo, 13 Albert VuliVuli, 12 Andrea Masi, 11 Julien Saubade, 10 Jerome Fillol, 9 Nicolas Durand, 8 Sebastien Chabal, 7 Jacques Cronje, 6 John Leo'o 5 Jone Qovu Nailiko 4 Lionel Nallet 3 Juan Pablo Orlandi 2 Benjamin Noirot 1 Andrea Lo Cicero
Replacements: 16 Carlo Festuccia 17 Scott Zimmermann 18 Julien Brugnaut 19 Santiago Dellape 20 Mathieu Loree 21 Mirco Bergamasco 22 Remi Vaquiin 23 Antoine Batut