Leinster opened Pool Six of the Heineken Cup right up with a terrific 32-7 win over the Scarlets atr Parc y Scarlets on Saturday.
The Leinstermen were in scintillating form, racking up a 22-0 lead within a half-hour with three magnificent tries and holding that lead until half-time. By half-time, stats said the Leinster players had beaten 13 defenders between them. The Scarlets had beaten 13 fewer than that. In a bombastic first half, played at a frantic pace, that was by far the most telling statistic.
The second half was more even - it could barely failed to have been - and the Scarlets threatened even to be fighting back into proceedings until Sean Lamont's asinine shoulder charge on Man of the Match Isa Nacewa which cost him ten minutes in the sin-bin and his team three precious points.
Thereafter it was only about whether Leinster could grab the bonus point try or not. It eventually came with nine minutes to go after a clean break by Shaun Berne, carry by Jamie Heaslip and sliding finish from openside Sean O'Brien. It was no more than Leinster deserved.
It took just three minutes and 15 seconds for Leinster to cross for their opening try when winger Horgan sped through a gap between Andy Fenby and Daniel Evans and rounded two more tacklers on a 40-metre run to the line.
Berne converted and then added a penalty before Leinster scored two more tries in five minutes.
The lively Isa Nacewa was sent down the wing by Brian O'Driscoll, who the home fans believed should have been in the sin-bin for a high tackle on Evans, before D'Arcy was sent over.
And Leinster cruised into a 22-0 lead after a quick Eion Reddan throw-in was moved quickly across the field for Berne to go over in the corner.
The Scarlets' intent to get on the scoreboard was obvious after the interval and five minutes into the half Davies forced his way over for a converted try.
That upped the tempo of the contest and more pressure from the Scarlets saw Leinster lock Nathan Hines sin-binned for a professional foul.
Although Leinster re-grouped, they missed a chance of a long-range penalty goal when Rob Kearney fired wide.
The atmosphere was stoked up even more when Sean Lamont was yellow-carded for an illegal challenge on Nacewa, which saw Berne kick Leinster into a 25-7 lead on 56 minutes.
As the match wore on Leinster must have started wondering where the fourth try was coming from, but it duly arrived on 72 minutes when Jamie Heaslip sent O'Brien in for the key score.
Man of the match: Take a bow Isa Nacewa, showing the northerners what open-play running is all about.
For the Scarlets:
Tries: Horgan, D'Arcy, Berne
Cons: Berne 2
Pens: Berne 2
Yellow cards: Hines (Leinster, 48, repeated infringements), Lamont (Scarlets, 56, dangerous tackle)
Scarlets: 15 Daniel Evans, 14 Andy Fenby, 13 Sean Lamont, 12 Jonathan Davies, 11 Lee Williams, 10 Stephen Jones, 9 Martin Roberts, 8 David Lyons (capt), 7 Richie Pugh, 6 Simon Easterby, 5 Dominic Day, 4 Lou Reed, 3 Deacon Manu, 2 Ken Owens, 1 Iestyn Thomas.
Replacements: 16 Emyr Phillips, 17 Phil John, 18 Jamie Corsi, 19 Vernon Cooper, 20 Rob McCusker, 21 Tavis Knoyle, 22 Rhys Priestland, 23 Gareth Maule.
Leinster: 15 Rob Kearney, 14 Shane Horgan, 13 Brian O'Driscoll, 12 Gordon D'Arcy, 11 Isa Nacewa, 10 Shaun Berne, 9 Eoin Reddan, 8 Jamie Heaslip, 7 Sean O'Brien, 6 Kevin McLaughlin, 5 Nathan Hines, 4 Leo Cullen (capt), 3 CJ van der Linde, 2 John Fogarty, 1 Cian Healy.
Replacements: 16 Bernard Jackman, 17 Mike Ross, 18 Stan Wright, 19 Malcolm O'Kelly, 20 Stephen Keogh, 21 Paul O'Donohoe, 22 Fergus McFadden, 23 Girvan Dempsey.
Referee: Chris White (England)
Assistant referees: Sean Davey (England), Stuart Terheege (England)
Television match official: David Mathews (England)