The Ospreys have named Matthew Morgan at fly-half for Friday's game against the Dragons in Swansea.
Morgan's promotion sees Dan Biggar move to full-back as Richard Fussell drops out of the squad altogether. Ashley Beck is also absent.
Up front, Aaron Jarvis replaces Wales prop Adam Jones while Morgan Allen wears eight in place of Joe Bearman for the derby fixture, with Steve Tandy looking to bounce back from last week.
"Obviously we are disappointed about Sunday but a game like this one is the perfect way for us to pick ourselves up and go again," he said.
"This group has plenty of fight and spirit and are determined to do themselves justice, starting on Friday night.
"This is an important time of the season for us, one where we have traditionally done well when the core group and the spirit they have pulls us through. It won't be any different this season.
"There'll be boys coming into the 23 who will see it as a real opportunity to stake a claim for a regular place and we"ll be encouraging that attitude as it will help to drive this squad on."
"It's a Welsh derby so that gives the game a bit of something extra."
Meanwhile, Dragons second-row Andrew Coombs returns to the starting XV this week.
The Ospreys currently sit in second place in the RaboDirect PRO12 league table as the Dragons sit in sixth; second out of the Welsh regions.
"We are sitting sixth in the league and it's not something that we have achieved for a number of years. It's been a fantastic start but it's all about keeping it going," said skipper Coombs.
"The Ospreys are going to be hurting a lot after their losses, including two Heineken cup games, but it's going to be a difficult evening for us. I am sure if we start as we started against Scarlets, full of confidence and ambition to run the ball, we just need to go there and challenge them.
"Whenever you play the Ospreys it's always going to be difficult because of the quality of players they have. They know how to turn things around they have been in this position before and they have come through it before. No doubt on Friday night they are going to be on fire and it's just important that we are on top of our game to win that match."
Lyn Jones has made seven changes to his team for the RaboDirect PRO12 game.
He makes only one change in the back three as Tom Prydie is on the wing; both Hallam Amos and Dan Evans keep their places from last week. The centre pairing takes on a slightly different look with Lewis Robling who makes his season debut for the Dragons.
Italy fly-half Kris Burton gets his third start of the season and is alongside Richie Rees.
There is only one change in the front-row as young gun Sam Parry steps in as hooker and Hugh Gustafson moves to the bench. Matthew Screech also keeps his place alongside skipper Coombs in the second-row. There is only one change in the back row with Jevon Groves moving into the flanker position, alongside Lewis Evans and Toby Faletau.
Form: Ospreys have slipped to three straight defeats in all competitions, two of those encounters being played at Liberty Stadium, where they have not lost three in a row since 2004. The Swansea based side had the better of their last eight encounters with fellow Welsh regions in the RaboDirect PRO12, whilst the last Welsh region to beat Ospreys at Liberty Stadium was the Dragons themselves in October 2010. Newport Gwent Dragons' last ten fixtures in all competitions have been won by the home side on the day. The Dragons have not won on the road since a 14-13 victory at Zebre in February. The Men from Gwent have only ever won three away games at fellow Welsh regions in 33 attempts in all competitions. The Dragons have not beaten Ospreys in the PRO12 since 6th January 2012 at Rodney Parade, but did do so in the Anglo Welsh Cup last season. Dragons have won only one of their previous eight visits to Liberty Stadium.
Ospreys: 15 Dan Biggar, 14 Jeff Hassler, 13 Jonathan Spratt, 12 Andrew Bishop, 11 Eli Walker, 10 Matthew Morgan, 9 Tom Habberfield, 8 Morgan Allen, 7 Justin Tipuric, 6 Tyler Ardron, 5 James King, 4 Alun Wyn Jones (capt), 3 Aaron Jarvis, 2 Richard Hibbard, 1 Ryan Bevington.
Replacements: 16 Scott Baldwin, 17 Duncan Jones, 18 Adam Jones, 19 Lloyd Peers, 20 Joe Bearman, 21 Tito Tebaldi, 22 Ben John, 23 Sam Lewis.
Dragons: 15 Dan Evans, 14 Tom Prydie, 13 Ross Wardle, 12 Lewis Robling, 11 Hallam Amos, 10 Kris Burton, 9 Richie Rees, 8 Toby Faletau, 7 Lewis Evans, 6 Jevon Groves, 5 Andrew Coombs (c), 4 Matthew Screech, 3 Dan Way, 2 Sam Parry, 1 Owen Evans.
Replacements: 16 Hugh Gustafson, 17 Nathan Williams, 18 Francisco Chaparro, 19 Adam Jones, 20 Ieuan Jones, 21 Jonathan Evans, 22 Will Harries, 23 Adam Hughes.
Date: Friday, October 25
Kick-off: 19:05 BST
Venue: Liberty Stadium
Referee: Nigel Owens (Wales)
Assistant referees: Leighton Hodges (Wales), Jon Mason (Wales)
Television match official: Tim Hayes (Wales)