That yellow card could prove costly for Castres. They've been on top this whole half but he's put his team in an extremely awkward postion being a man down against a side like Leinster.
Great jump from Wannenburg to win the ball at the lineout and they get the penalty as he is tackled in the air.
Poor play from Lamerat as he is sent to the bin for going into the tackle with no arms. Leinster go into the corner.
Game has slowed due to a number of subs. McGrath and Roux on for Healy and McCarthy respectively.
Kick is just wide from Kockott. Tough kick for Kockott. Still 9-7 after 53 minutes.
Heaslip penalised for being off his feet in the ruck and Isaac Boss points to the posts. Has a chance to put his side in the lead.
Go leinster
Crowd urging Leinster on in defence and it has worked. Leinster confident in defence and turn the ball over.
Yes
Castres firmly on top here. Leinster change as Eoin Reddan comes on to replace Isaac Boss.