Adam Jones will make his 150th Ospreys appearance against Scarlets in their Boxing Day Pro12 Welsh derby at Parc Y Scarlets.
The Scarlets' last game of the year will be in front of a full house as the Ospreys travel West to their nearest and oldest rivals.
It will be another record crowd in the history of Parc y Scarlets with 14,800 (capacity at the stadium) set to attend.
Back from injury is Scarlets and Wales winger George North who starts on Monday 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," said Davies.
"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."
Meanwhile, Ospreys Director of Coaching Scott Johnson said his team faced a "real test".
"There's always a lot of pride at stake in these derby fixtures, on and off the pitch, and it's not going to be any different on Monday," said Johnson.
"You've got two teams who will be stinging a little bit after the disappointment of the last two weeks in Europe, but what I can guarantee you is that we are itching to get back into it and want to make the fans proud of this team in a big game that will have all the intensity of Europe.
"Traditionally we've hit some kind of form over this period with the players spending a prolonged spell in camp with us. Clearly things have been a little different this year with the December international disrupting things for all the regions, but it's hugely important for us if we want to cement our place in the play-off spots that we get that consistency into our game."
Form: Scarlets have slipped to three straight defeats in all competitions, but have won their last three games at Parc y Scarlets in the RaboDirect PRO12. Scarlets are unbeaten in their last four clashes with fellow Welsh regions, whilst they have not lost at home in a Welsh derby since Ospreys were the visitors on 2 October 2010. Ospreys only reversal this season in the RaboDirect PRO12 was 17-28 at Glasgow Warriors in round seven. Ospreys are winless in their last four fixtures against fellow Welsh regions. Scarlets have not beaten Ospreys since a 17-12 victory at the old Stradey Park on 27 December 2007.
Scarlets: 15 Liam Williams, 14 George North, 13 Scott Williams, 12 Jon Davies, 11 Sean Lamont, 10 Rhys Priestland, 9 Gareth Davies, 8 Ben Morgan, 7 Rob McCusker, 6 Aaron Shingler, 5 Dominic Day, 4 Lou Reed, 3 Rhys Thomas, 2 Matthew Rees (capt), 1 Rhodri Jones.
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.
Ospreys:15 Barry Davies, 14 Tommy Bowe, 13 Andrew Bishop, 12 Ashley Beck, 11 Shane Williams, 10 Dan Biggar, 9 Kahn Fotuali'i, 8 Joe Bearman, 7 Justin Tipuric (c), 6 Tom Smith, 5 Jonathan Thomas, 4 Ryan Jones, 3 Adam Jones, 2 Richard Hibbard, 1 Paul James.
Replacements: 16 Mefin Davies, 17 Ryan Bevington, 18 Aaron Jarvis, 19 James King, 20 George Stowers, 21 Rhys Webb, 22 Matthew Morgan, 23 Hanno Dirksen,
Date: Monday 26 December
Venue: Parc y Scarlets
Kick-off: 14.05 GMT
Referee: Nigel Owens