Ospreys boss Steve Tandy has made four changes to his starting line-up for Friday's derby with the Scarlets at the Liberty Stadium.
Into the side comes British and Irish Lions forwards Justin Tipuric and Ian Evans, starting at openside flanker and second-row respectively.
In the backs, Aisea Natoga starts on the wing, with Aaron Jarvis the fourth change at tighthead.
Jarvis' front row colleague, veteran loosehead Duncan Jones, makes his 200th appearance for the region.
"While we got the win at Parc y Scarlets last week, in many ways it was a frustrating afternoon," said Tandy.
"The spirit, effort and commitment from the team was faultless, but we made too many basic errors, coughed up possession cheaply and that meant we found ourselves under pressure.
"The message this week is about raising that performance level so that it meets the standard we expect as Ospreys. We've got some big games over the next few weeks, with the Heineken Cup looming after Scarlets on Friday, and we know that we need to be performing at our very best if we are going to achieve what we want in these games."
Meanwhile, Scarlets head coach Simon Easterby said that his players would look to reward themselves for the hard work and effort that has gone into their last two performances by securing a victory in the return fixture of the Welsh derby in the West on Friday.
With such tight score lines and competitive performances in both their fixtures against Munster and then the Ospreys last time out, the Scarlets boss said his team deserved to get a result this weekend.
However, the Scarlets know they have a tough task ahead to get a win at the battleground of the Liberty Stadium but added that had given enough in both their recent performances against table topping sides Munster and the Ospreys to win both games -with only one score's difference between the Scarlets and their opposition in both fixtures.
"The players have responded well in training this week after the disappointment of Boxing Day, and it's good to have the Welsh derbies back-to-back for many reasons; it's good in terms of preparation during the week to play the same team again and it gives our players an edge and leaves a taste in the mouth with the desire to put right the previous performance," said Easterby.
"And for our supporters there's something to get behind as well in terms of giving the players a lift, particularly as it's against our nearest rivals. The support over the festive period in these Welsh derbies has been brilliant and we should applaud our supporters for really showing their loyalty to regional rugby by backing us in big numbers at our games.
"It's going to be another packed night at the Liberty as well in a very positive way to round off the festive derby series."
Form: Ospreys have won their last three matches in all tournaments since their 9-15 defeat in Castres in the European Cup on December 6. Ospreys were defeated in their last PRO12 fixture at Liberty Stadium, 16-28 to Glasgow, just their second home defeat in the competition since September 2012. Ospreys have not lost at home to a fellow Welsh Region in the PRO12 since Dragons visited the Liberty Stadium in October 2010. Scarlets have slipped to five straight losses in all tournaments since winning 24-21 in Connacht in the PRO12 on November 23. Scarlets only victory in their last eleven encounters with Ospreys since 2007 was 22-14 at Parc y Scarlets on Boxing Day 2011, whilst Scarlets only previous win at Liberty Stadium was 14-9 on September 11 2007.
Ospreys: 15 Sam Davies, 14 Aisea Natoga, 13 Ben John, 12 Ashley Beck, 11 Jeff Hassler, 10 Dan Biggar, 9 Rhys Webb, 8 Joe Bearman, 7 Sam Lewis, 6 Justin Tipuric, 5 Ian Evans, 4 Alun Wyn Jones, 3 Aaron Jarvis, 2 Richard Hibbard, 1 Duncan Jones
Replacements: 16 Scott Baldwin, 17 Ryan Bevington, 18 Adam Jones, 19 James King, 20 Morgan Allen, 21 Tyler Ardron, 22 Tom Habberfield, 23 Richard Fussell
Scarlets: 15 Gareth Owen, 14 Kristian Phillips, 13 Nick Reynolds, 12 Scott Williams, 11 Frazier Climo, 10 Rhys Priestland, 9 Rhodri Williams, 8 Rob McCusker (c), 7 John Barclay, 6 Josh Turnbull, 5 George Earle, 4 Jake Ball, 3 Samson Lee, 2 Emyr Phillips, 1 Phil John
Replacements: 16 Kirby Myhill, 17 Rob Evans, 18 Jacobie Adriaanse, 19 Johan Snyman, 20 Aaron Shingler, 21 Gareth Davies, 22 Aled Thomas, 23 Jordan Williams.
Date: Friday, January 3
Kick-off: 19:15 GMT
Venue: Liberty Stadium
Referee: Nigel Owens (Wales)
Assistant referees: Ian Davies, Jon Mason (both Wales)
Television match official: Derek Bevan (Wales)