Welcome to coverage of the Heineken Cup clash from Thomond Park. Munster have been in fearless form, winning four from four, but this will be a tough one…

Here are the teams…

Munster: D Hurley; J Murphy, K Earls, L Mafi, S Zebo; R O’Gara, C Murray; W du Preez, D Varley, BJ Botha; D Ryan, P O’Connell; P O’Mahony, N Ronan, J Coughlan.
Replacements: D Fogarty, M Horan, S Archer, D O’Callaghan, B Holland, T O’Leary, I Keatley, D Barnes.

Castres: R Martial; V Inigo, P Bonnefond, P-M Garcia, P-G Lakafia; P Bernard, T Lacrampe; S Taumoepeau, M-A Rallier, A Peikrishvili; M Rolland, R Capo Ortega; Y Caballero, S Malonga, J Bornman.
Replacements: M Bonello, M Coetzee, K Wihongi, S Murray, I Diarra, R Kockott, S Bai, M Nicolas.

Munster 0-0 Castres: It’s a sell-out crowd at Thomond Park and the crowd is in great song as Ronan O’Gara gets the match under-way.

As the game settles down, it’s worth mentioning that a Munster win would secure a knockout spot and also move them one step closer to a lucrative home quarter-final. They are hot favourites to win at a price of 1/40, with Castres at 12/1.

Munster 0-0 Castres: Donncha Ryan flies forward and the ball falls to Mafi. It would have been a try had James Coughlan found Damien Varley, but Castres intervene at the last second.

All made by Ryan’s excellent football skills.

Munster 7-0 Castres: A training ground move from the line-out, with Ryan and Conor Murray teaming up to find Johne Murphy. It was soft defending by Castres and he took his try with ease. O’Gara converts, predictably.

Munster 7-0 Castres: BJ Botha is penalised and Pierre Bernard misses Castres’ first attempt at a penalty. It may be early in the game but a Munster in this kind of form will punish such wastefulness.

Meanwhile, Niall Ronan has been carried off with what looks like a serious injury. There was nobody around him so the worst is feared. Donncha O’Callaghan comes on to replace him.

Munster 10-0 Castres: A great strike from O’Gara, as his penalty puts two scores in the difference. Castres will be sick of the sight of the fly-half, following his heroics earlier in the season.

Munster 10-7 Castres: Yannick Caballero makes the most of a great touch from Taumoepeau, as Castres catch the Irish province napping. Excellent improvisation, and Bernard nails the conversion. Good to know we have a game here.

Munster 13-7 Castres: Castres are off-side and O’Gara is not about to turn down three easy points.

Munster 13-7 Castres: Lacrampe and Caballero save Castres as Munster zig zag towards the line. Simon Zebo and Denis Hurley are central to the move, with O’Gara and Ryan also involved, but the French side snuff out the danger.

Munster 16-7 Castres: It’s all for nothing, though, as Castres are penalised and O’Gara cannot miss from under the posts.

Munster 16-7 Castres: Tremendous work from O’Connell and the Munster pack as Caballero and co. get to within two or three yards of the line.

Castres powerhouse Ortega was central to that move. A mountain of a man.

Munster 16-7 Castres: Castres keep getting caught trying to wheel the Munster scrum around. Tony McGahan’s side will take that all day.

Munster 16-7 Castres: O’Gara finds the corner brilliantly after Earls’ kick to Zebo is a little bit sloppy. The veteran is on top of his game today.

Munster 16-7 Castres: A penalty to Castres on their own line. Munster made a few yards but James Coughlan is eventually penalised.

An intense half is brought to a close.

Munster 16-7 Castres: We’re back, and Munster have come out with added vigour in this half. Just as we say that, though, they give away a penalty.

Munster 16-10 Castres: We finally have the first score of the second half, and it goes to the boot of Bernard. Munster are rattled.

Shortly afterwards, Ortega is punished for pulling a Munster player by the head. Animal. O’Gara has a chance to cancel out the earlier three points - and it comes off the post.

Munster 16-10 Castres: With the exception of the brilliant O’Gara, Munster seem to be lacking both experience and leadership. They may have the lead but this has been anything but an electric performance.

Munster seem edgy but, while the crowd urge them on, Murphy’s try seems like ages ago.

FULL-TIME: Chelsea 1-0 Sunderland

Martin O’Neill loses for just the second time with Sunderland, but they scarcely deserved it. Andre Villas-Boas will be glad of the cleansheet, as David Luiz was wojious today.

Munster 19-10 Castres: The head says Munster should kick this penalty, the heart says to run it. The head wins. O’Gara scores. Nine points in it.

Castres have conceded 11 penalties to Munster’s six.

Munster 19-10 Castres: The crowd exalts as Murray goes under the posts, but the try is not given as O’Connell needlessly impeded Peikrishvili. That was foolish from someone who should know better. Lacrampe, meanwhile, is in the sin bin for seven more minutes.

Munster 19-10 Castres: Peter O’Mahony’s pass to O’Connell is spilled by the Irish captain. The match is turning into a drudge, as Castres’ lack of discipline is preventing them from offering any challenge to the below par home side.

Munster 19-10 Castres: Tomás O’Leary replaces Conor Murray as Munster continue to handle badly and needlessly break down the flow of the game. A spark must come from somewhere…

Munster 26-10 Castres: It’s over to the TMO to see if a try from Munster’s loosehead prop Wian du Preez – after good work from Lifeimi Mafi - should stand. It should. That was sheer, dogged determination and he just makes it over. O’Gara adds the extras.

Munster 26-10 Castres: A great day for the Munster scrum, at least. Donncha Ryan congratulates his front row as the home side wins another penalty. Ryan, incidentally, has been named man of the match and deservedly so.

The Munster pack has worked hard all day and they’ve met a tough team, it’s just a pity that the game has not flowed better.

Munster 26-10 Castres: That is that. Munster may not be playing particularly well but they’ve just secured their fifth win from five games. They have qualified for the quarter-finals and go to Northampton next week to decide whether their last eight clash will be home or away.

Thanks for keeping up…