Leinster 33-3 Castres

Leinster strengthened their position at the top of Heineken Cup pool two as a trio of second-half tries helped them see off the challenge of Castres Olympique at the RDS.

Bernard Jackman, Brian O'Driscoll and replacement Simon Keogh all crossed the French side's whitewash but Leinster's push for a bonus point try came too late.

On the balance of play and for all their effort, the Irish province would not have deserved the extra point as they were lacklustre in attack for much of this game.

Castres travelled with a mostly second string line-up - injured captain Lionel Nallet was among those missing - and they kept big guns like All Blacks Chris Masoe and Carl Hoeft and quality place kicker Romain Teulet in check for next week's return match.

Currently second-from-bottom in the French Championship, the visitors made some early headway with Kevin Senio and Steve Kefu getting ball in hand.

They engineered the first scoring chance after Malcolm O'Kelly had infringed at a midfield ruck, but Anthony Lagardere's second-minute effort dropped under the crossbar.

Leinster made some uncharacteristic handling errors early on and it was the line-out where they looked most assured, with man-of-the-match Devin Toner literally head and shoulder above everyone in the set piece.

With Felipe Contepomi absent due to a hand infection, Jonathan Sexton started at number 10 and he showed his worth with three sure-footed penalty kicks - after 14, 19 and 29 minutes - which handed Leinster a 9-0 half-time lead.

The hosts' try-scoring opportunities were limited in the opening half.

After lineout steals from Elsom and O'Kelly, the former spilled the ball in contact just inches from the line. Stan Wright also went close to breaking the deadlock and Lagardere had to be alert to thwart an advancing O'Driscoll.

Castres lost South African flanker Darron Nell to a knee injury before the interval and coming under more pressure on the restart, they buckled.

Shane Horgan kicked into space, got a favourable bounce and was able to off-load for the supporting Jackman to score close to the posts in the 47th minute.

Sexton tapped over the conversion and though Lagardere replied with a well-struck penalty for Castres, Sexton was able to cancel that score out with his fourth penalty success after replacement prop Yannick Forestier had been sin-binned.

After a near miss when Jamie Heaslip almost embarrassed Lagardere on his own try-line, Leinster took their chances in the final 13 minutes, adding two more tries.

O'Driscoll, scoring his fourth try in this season's tournament, touched down from close range before a hamstring injury ended his afternoon.

Then Keogh darted over with three minutes remaining, after linking with Wright and fellow replacement David Holwell.