It will be another record crowd in the history of Parc y Scarlets of 14,800 (capacity at the stadium) - this time for a league fixture as the RaboDirect PRO12 festive battle kicks off at 2.05pm on Boxing Day.
The Scarlets will field a strong side to take on the might of the Ospreys after drawing 9-9 in a tightly fought contest at their trip to the Liberty in November. The Scarlets have won their last three games at home at Parc y Scarlets in the RaboDirect PRO 12 and are unbeaten in their last four clashes with fellow Welsh regions.
The Scarlets have not lost at home in a Welsh derby since the Ospreys visited in October 2010 however have not beaten the Ospreys since a 17-12 victory at Stradey Park in the corresponding festive fixture in 2007. The Ospreys are winless in their last four fixtures against fellow Welsh regions.
Back from injury, is Scarlets and Wales winger George North who starts on Monday afternoon after recovering from a dead leg suffered in the Australia international in early December. Second row Damian Welch is not available for selection after suffering a fractured thumb against Munster last weekend.
Rhys Priestland comes back to take the 10 shirt, with Gareth Davies retained at scrum-half to start after his impressive form creating quick ball this season.
Head of Rugby Nigel Davies said it was difficult to be dispassionate and not that emotional about these historic derby encounters but said the Scarlets were looking forward to a very big rugby occasion.
"It's a fantastic game of rugby in store and with quality across the field from both sides, there will be some great contests to watch and it should be a great occasion for our supporters.
"To have such a great history and sense of rivalry just adds to the excitement around the game. We have a sell-out stadium, which will be a real boost to the players - it's good to see so much interest in this fixture and shows what regional rugby is capable of bringing in terms of a spectacle for supporters.
"But you can't afford to be too emotional, there's a lot of passion underneath; but we have been firmly focused and single-minded on what we need to do to achieve victory this week. It was very close last time out, and we'll have to bring a level of intensity and accuracy that will be all-important and - desire. But there won't be any shortage of that from either team."
Davies said that with just a four-day turnaround until their next fixture, post Ospreys the Scarlets have adjusted their week to train specifically with two teams for the two fixtures head-to-head this week.
He said: "There's such a tight turnaround for us - just four days, and you have to consider how intense these matches are and it's too tight a timeframe to expect them all to front up again. So we are managing this and trained differently this week that has really energised the group.
"It's a positive is that our squad is strong enough and has the depth to do this right now. For many of our players, it's a major opportunity to show up in two big games ahead of our next block of rugby.
"There's not a lot in two teams we had training this week, both are well-balanced and very competitive and all-in-all it's a good sign for the future of our squad."
Scarlets team against Ospreys 26th December 2011, Parc y Scarlets kick off 2.05pm: 15 Liam Williams, 14 George North, 13 Scott Williams, 12 Jon Davies, 11 Sean Lamont, 10 Rhys Priestland, 9 Gareth Davies, 1 Rhodri Jones, 2 Matthew Rees (capt), 3 Rhys Thomas, 4 Lou Reed, 5 Dominic Day, 6 Aaron Shingler, 7 Rob McCusker, 8 Ben Morgan.
Replacements: 16 Ken Owens, 17 Phil John, 18 Deacon Manu, 19 Sione Timani, 20 Johnathan Edwards, 21 Rhodri Williams, 22 Stephen Jones, 23 Iongi Viliame.
Rhys Priestland said: "It's probably the fixture of the year for our supporters and Parc y Scarlets is a special place to play when it's full so it will be a great occasion.
"Obviously every player appreciates the support that we get, and we are very fortunate that the Scarlets supporters make a real effort. We all respect that commitment and so we try reward the supporters with our style of rugby and giving them something to enjoy watching. As Scarlets we just go out and try and play with our heads up."
"We have failed in the last two weeks and that's a big disappointment for us and it's time we started to cross the line and begin to beat these teams, rather than coming close second. We have to find the balance between playing attractive rugby, that is our way and crossing that line. What we know is that if we turn up in the right frame of mind, and get it right on the pitch - we can mix it with the best teams. What we're not going to do is hide from playing.
Priestland said 2011 had been a great year for him with more to look forward to in 2012. "I have thoroughly enjoyed my rugby this year and have been lucky to get my first cap and going to the World Cup was great for me. I just want to enjoy the game and better myself. I'll keep working hard, practice and focus and keep improving my game."
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