SCARLETS (1st) v MUNSTER (2nd), Parc y Scarlets, 3.40pm (live Sky Sports 1/HD1)

Team News: Munster have kept the same pack of forwards that they had against Castres Olympique in round 2 for the trip to Llanelli to face Pool 3 leaders Scarlets on Saturday.

There are four changes in the back-line, one of course necessitated by the Achilles injury to Doug Howlett. The 21-year-old Simon Zebo slots in on the left wing despite an injury scare earlier in the week when he hurt his ankle.

Zebo will be making his Heineken Cup debut on the day that vastly-experienced out-half Ronan O'Gara becomes only the second player to win 100 Heineken Cup caps - O'Gara's long-time provincial team-mate John Hayes was the first.

Will Chambers, who was used as a replacement against Castres, starts on this occasion, with the player he replaced that day, Danny Barnes, dropping to the bench

Otherwise the other changes are positional, Johne Murphy donning Howlett's number 14 jersey and Denis Hurley staying at full-back where he has impressed in the most recent games against Edinburgh and Ospreys.

While acknowledging the Scarlets' strength behind the scrum, the province's captain Paul O'Connell has also noted the improvements they have made up front.

"Obviously you have guys like (Rhys) Priestland, (Jonathan) Davies and (George) North which will give us something to focus on, they were probably the stars for Wales in the World Cup," he said.

"But they did really well in the scrum against Northampton, they have a good lineout and they've been playing as a unit now for a while.

"The World Cup hasn't disrupted them that much, they don't have to rest players (as decreed by the Welsh Rugby Union), so they've been playing together quite a bit and they've done really well up front.

"Simon Easterby is involved with them and he's a guy we would know well. I would have had great respect for Simon as a player, I know what he is made up of and he is mentally very strong.

"He will look to have instilled that in the Scarlets players. They're a very good forward unit - any team that can go away to Northampton, win well and pick up a bonus point has to have a serious pack."

Meanwhile, Scarlets boss Nigel Davies has made just one change to the team that beat Northampton Saints at Franklin's Gardens last time out in Europe.

Johnathan Edwards drops to the bench, making way for the fit-again Rob McCusker who lined out at openside flanker in the region's 24-27 league defeat at Ulster last weekend.

George North and Jonathan Davies, two players who impressed during Wales' successful World Cup campaign, have shaken off their respective injuries to start.

Scarlets captain Matthew Rees and Rhys Priestland are also back from Wales duty, with the latter being preferred to the more experienced Stephen Jones at out-half. Gareth Davies has held onto the number 9 jersey ahead of Tavis Knoyle.

The Scarlets come into Saturday's game with one loss in nine outings in all competitions. The Celtic contest has captured the imagination of supporters both sides of the Irish Sea with around 2,000 travelling Munster supporters making the West Wales trip and a packed home crowd of more than 12,000 expected.

SCARLETS: Liam Williams; George North, Scott Williams, Jonathan Davies, Sean Lamont; Rhys Priestland, Gareth Davies; Iestyn Thomas, Matthew Rees (capt), Rhys Thomas, Sione Timani, Damian Welch, Aaron Shingler, Rob McCusker, Ben Morgan.

Replacements: Ken Owens, Phil John, Deacon Manu, Kieran Murphy, Johnathan Edwards, Tavis Knoyle, Stephen Jones, Viliame Iongi.

MUNSTER: Denis Hurley; Johne Murphy, Will Chambers, Lifeimi Mafi, Simon Zebo; Ronan O'Gara, Conor Murray; Wian du Preez, Damien Varley, BJ Botha, Donnacha Ryan, Paul O'Connell (capt), Peter O'Mahony, Niall Ronan, James Coughlan.

Replacements: Denis Fogarty, Marcus Horan, John Hayes, Donncha O'Callaghan, Denis Leamy, Tomas O'Leary, Ian Keatley, Danny Barnes.

Referee: Romain Poite (France)
Assistant Referees: Cyril Lafon, Stephane Boyer (both France)
Television Match Official: Jean-Pierre Pellaprat (France)

Match Odds (Paddy Power): Scarlets to win: 8/11; Draw: 20/1; Munster to win: 11/10

Pre-Match Quotes: Ronan O'Gara (Munster) - "I was honoured to present John Hayes with his cap for reaching 100 Heineken Cup matches. He was the most fitting Munster man to achieve that milestone.

"It is a great thing to achieve, but I don't look upon it as anything big at this stage. When I retire in a few years' time I will look back on it as being a significant cap because it is such a fantastic competition.

"It is a competition that has given me every possible emotion - and that's why you play the game. I have had wonderful moments and disappointing moments, but that's why you get involved in sport and that's why this team is so special to me and why the fans are so loyal to the Heineken Cup - it is a wonderful ambassador for northern Hemisphere rugby.

"It was popular at certain stages throughout the season, but the support bases that Munster, Ulster, Leinster have built, and now Connacht, have been phenomenal. It is real a tribute to what these provinces have done.

"When we played Leinster in Dooradoyle in 1997 there were 500 people there. Now we can get 80,000 for a Heineken Cup clash between the same two teams.

"That shows the impact the game has in this country and it doesn't happen by chance - there has been a lot of hard work done by the provinces, ERC and Heineken.

"The fascinating thing about the Heineken Cup is it is a club competition. People miss that point sometimes. You have some of the best players in your country on the team and then some younger players who are trying to develop who wouldn't get on an international side.

"What is so good about the Heineken Cup is the game that can be played - you have more time on the ball. You have a second longer than you would have in international rugby.

"That's the key difference. There are opportunities for mismatches whereas at international level that doesn't happen, which is why it is a slightly less appealing game to the fans."

Nigel Davies (Scarlets) - "There's obviously a lot of tension building for this game but we've kept things very focused and there's a great atmosphere in the group and the energy and motivation levels are very high.

"The boys have responded really well this week and I've never had such a difficult job in terms of selection - there's been some really tight calls.

"This is a two-series game and it's going to akin to international rugby over the next two fixtures with the quality you have on the field and the intensity that both sides will bring.

"We got a big result away from home against Northampton, but we must back that up now at home and we know full well the challenge we face against Munster.

"They bring such a strong desire and will to win and a great team spirit. We all know they are a fantastic team and the threats they have on the field - they have great traditions and represent their community well and have rugby values that mirror our own.

"Simply we have to match that and then bring an intensity and physicality to this game, where they have been able to get the better of us in the past.

"The boys have shown they can do that in our opening two games in Europe and we know we have the talent in the back-line to score points and now it's about bringing intensity throughout our game on the big day."

Current Form - Scarlets - (RaboDirect PRO12): Won 32-9 at home to Aironi Rugby; Lost 13-11 away to Connacht; Lost 35-12 away to Munster; Lost 15-10 at home to Leinster; Lost 20-10 away to Benetton Treviso; Won 33-17 at home to Edinburgh; Won 24-17 at home to Ulster; Drew 9-9 away to the Ospreys; (Heineken Cup): Won 31-23 at home to Castres Olympique; Won 28-23 away to Northampton Saints; (RaboDirect PRO12): Won 22-12 at home to the Newport Gwent Dragons; Lost 24-17 away to Ulster

Munster - (RaboDirect PRO12): Won 20-12 at home to the Newport Gwent Dragons; Won 23-12 away to Glasgow Warriors; Won 35-12 at home to the Scarlets; Won 18-13 away to the Cardiff Blues; Lost 29-14 away to Edinburgh; Lost 17-13 at home to the Ospreys; Won 18-6 at home to Aironi Rugby; Lost 24-19 away to Leinster; (Heineken Cup): Won 23-21 at home to Northampton Saints; Won 27-24 away to Castres Olympique; (RaboDirect PRO12): Won 34-17 at home to Edinburgh; Lost 19-13 away to the Ospreys

Top Scorers - 2011/12 Heineken Cup: Scarlets - Points: Rhys Priestland 16; Tries: Sean Lamont, Ben Morgan, Jonathan Davies, Liam Williams, Aaron Shingler, Matt Gilbert, Rhys Priestland 1 each; Munster - Points: Ronan O'Gara 25; Tries: Doug Howlett 2

Previous European Meetings: 3

Sunday, December 16, 2007 - Pool 5 - Munster 22 Scarlets 13, Thomond Park
Saturday, December 8, 2007 - Pool 5 - Scarlets 16 Munster 29, Stradey Park
Friday, March 30, 2007 - Quarter-final - Scarlets 24 Munster 15, Stradey Park

Heineken Cup Records:

Scarlets -
2010/11: Failed to qualify from Pool 5
2009/10: Failed to qualify from Pool 6
2007/08: Failed to qualify from Pool 5
2006/07: Reached the semi-finals
2005/06: Failed to qualify from Pool 6
2004/05: Failed to qualify from Pool 3
2003/04: Reached the quarter-finals
2002/03: Reached the quarter-finals
2001/02: Reached the semi-finals
2000/01: Failed to qualify from Pool 5
1999/00: Reached the semi-finals
1998/99: Reached the quarter-finals
1997/98: Reached the quarter-final play-off
1996/97: Reached the quarter-finals

Munster -
2010/11: Failed to qualify from Pool 3
2009/10: Reached the semi-finals
2008/09: Reached the semi-finals
2007/08: Champions
2006/07: Reached the quarter-finals
2005/06: Champions
2004/05: Reached the quarter-finals
2003/04: Reached the semi-finals
2002/03: Reached the semi-finals
2001/02: Runners-up
2000/01: Reached the semi-finals
1999/00: Runners-up
1998/99: Reached the quarter-finals
1997/98: Failed to qualify from Pool D
1996/97: Failed to qualify from Pool D
1995/96: Failed to qualify from Pool D