The home side outscored the visitors by four tries to two in a scintillating Heineken Cup clash in the Irish capital and move to the top of Pool 2 after this impressive win.

Dean Ryan's youthful outfit will take plenty of heart from the way they played in the intimidating surroundings of this famous old ground.

But ultimately Malcolm O'Kelly and his Leinster pack had too much up front, while the home side's classy backs took their opportunities when they arose.

Leinster scored tries through Gordon D'Arcy, Stephen Keogh and Shane Horgan while fly-half Felipe Contepomi scored a try and kicked seven kicks from seven for a personal haul of 22 points.

The visitors responded with scores from Mark Foster and 20-year-old centre Jack Adams, who, along with midfield partner Anthony Allen, will have learned greatly from the experience of playing against D'Arcy and Brian O'Driscoll.

Fly-half Ryan Lamb added 10 points from the boot as Gloucester showed enough to suggest they will contest the pool strongly in front of a crowd of 22,530.

Leinster opened the scoring in the second minute when D'Arcy received Contepomi's pass on an arcing run before slipping out of Adams' tackle and scorching over.

Contepomi added the extras before Gloucester responded with a neat break from Allen that led to a penalty converted by Lamb.

The visitors struck again in the ninth minute when Peter Richards went on a clever looping run before slipping the ball to Foster.

The winger hit the line on the perfect angle before burning off O'Driscoll to score. Lamb's conversion made it 10-7 to the visitors.

Leinster scored their second try after just 13 minutes when Contepomi's chip ricocheted wickedly off Allen and on to the post, enabling the Argentinian to flop on the ball and score.

Contepomi added the conversion before stretching his side's lead to 13 points with three well-struck penalties in the space of 10 minutes as Leinster's pack began to take a grip on proceedings.

Leinster's third try came four minutes before the break when Iain Balshaw was unable to gather Lamb's pass allowing D'Arcy to gather the ball and speed away up field.

The centre fed Denis Hickie whose weaving run was eventually ended by a despairing tackle from James Bailey, but supporting flanker Keogh was on

hand to complete a length-of-the-field move. Contepomi's sixth successful kick made it 30-10 after 36 minutes.

Just as it looked as if Gloucester were dead and buried, Adams took a difficult pass from Lamb before stepping and dummying his way over from 15 metres for a memorable individual try. Lamb's conversion made it 30-17 to Leinster at the break.

Gloucester's cause was not helped when they lost openside Andy Hazell two minutes after the break with what looked like a shoulder injury, but they hung in valiantly and Lamb closed the gap to 10 points with a 48th-minute penalty.

Despite having Ireland lock Malcolm O'Kelly sent to the sin bin for a line-out infringement, Leinster came back strongly with a try from Horgan, converted by Contepomi, to make it 37-20 with less than a quarter to play.

The game ended in an air of farce when referee Christophe Berdos was forced off the field after an accidental collision with one of the players.

Gloucester pressed hard in the dying minutes, with replacement scrum-half Rory Lawson impressing, but were unable to break through a resolute home defence.

The scorers:

For Leinster:
Tries: D'Arcy, Contempomi, Keogh, Horgan
Cons: Contempomi 4
Pens: Contempomi 3

For Gloucester:
Tries: Foster, Adams
Cons: Lamb 2
Pens: Lamb 2

Leinster: 15 Girvan Dempsey, 14 Shane Horgan, 13 Brian O'Driscoll (c), 12 Gordon D'Arcy, 11 Denis Hickie, 10 Felipe Contepomi, 9 Cillian Willis, 8 Jamie Heaslip, 7 Keith Gleeson, 6 Stephen Keogh, 5 Malcolm O'Kelly, 4 Trevor Hogan, 3 Will Green, 2 Brian Blaney, 1 Ronan McCormack.
Replacements: 16 Harry Vermaas, 17 Reggie Corrigan, 18 Owen Finegan, 19 Cameron Jowitt, 20 Andy Dunne, 21 Kieran Lewis, 22 Luke Fitzgerald.

Gloucester: 15 Iain Balshaw, 14 James Bailey, 13 Jack Adams, 12 Anthony Allen, 11 Mark Foster, 10 Ryan Lamb, 9 Peter Richards, 8 James Forrester, 7 Andy Hazell, 6 Peter Buxton, 5 Adam Eustace, 4 Marco Bortolami (c), 3 Carlos Nieto, 2 Mefin Davies, 1 Christian Califano.
Replacements: 16 Nick Wood, 17 Olivier Azam, 18 Jonathan Pendlebury, 19 Jake Boer, 20 Rory Lawson, 21 Ludovic Mercier, 22 Rudi Keil.

Referee: Christophe Berdos