The Ospreys will be looking to bounce back from their 17-0 loss to Gloucester in the EDF Energy Cup by getting back on track in the Magners League at Ulster, but will be without a number of internationals.
The region were hit by a double blow this week, with Wales pair Gavin Henson and Jonathan Thomas being ruled out for the rest of the season.
Flanker Thomas has suffered a recurrence of a long-term groin problem, and has been advised to take three months recovery, while centre Henson was withdrawn during Saturday's semi-final against Gloucester and will out until early May.
Ian Gough was also taken off against Gloucester, suffering a haematoma in his hip, and will miss the Ulster clash but hopes to be fit for next weekend's match with Munster in the Heineken Cup quarter-final.
Lee Byrne remains on the sidelines as he recovers from damaged ligaments suffered in Wales's Six Nations finale against Ireland, while two other Welsh internationals in Shane Williams and captain Ryan Jones will not travel with the side to Northern Ireland.
Host Ulster had found form during the Six Nations break, having won both of their matches in this period, although like the Ospreys lost to Leinster in their last Magners League game.
Coach Matt Williams will be without Stephen Ferris, Bryn Cunningham and Paul Steinmetz but can call upon NiallO'Connor and Mark McCrea, who have been added to the squad for Friday night. And Williams is taking nothing for granted despite the Welsh region's weakened state.
"The Ospreys are a fantastic team and physically massive. No-one expects us to win so there isn't much pressure on us," said Williams.
"They are individually the best team in the competition with a big squad of very high quality players so it could be our toughest game at Ravenhill this season."
Forwards: Brendon Botha, Tom Court, Bryan Young, Ed O'Donoghue, Matt McCullough, Carlo del Fava, Chris Henry, Nigel Brady, David Pollock, Rory Best, Ryan Caldwell, Robbie Diack.
Backs: Simon Danielli, Andrew Trimble, Darren Cave, Cillian Willis, Niall O'Connor, Clinton Schifcofske, Ian Whitten, Isaac Boss, Ian Humphreys, Timoci Nagusa, Mark McCrea, Paddy Wallace.
Ospreys : Gareth Owen; David Bishop, Jonathan Spratt, Andrew Bishop, Jonny Vaughton; James Hook, Mike Phillips; Paul James (capt), Huw Bennett, Cai Griffiths, Alun Wyn Jones, Andy Lloyd, Tom Smith, Steve Tandy, Filo Tiatia.
Replacements: Richard Hibbard, Ryan Bevington, Filipo Levi, Marty Holah, Jamie Nutbrown, Dan Biggar, Sonny Parker.
WRU chief executive Martyn Phillips hosted the second meeting of the WRU Youth Board last weekend ahead of the Judgement Day IV regional double-header. Tthe board, made up of 15 under-21-year-olds from around Wales, heard presentations from head of participation Ryan Jones, policy and integrity manager Jeremy Rogers and national women's rugby manager Caroline Spanton, with Pro Rugby Wales CEO Mark Davies also on hand to hear the range of views aired.
Wales duo Rhun Williams and Liam Belcher, who makes a welcome return after five months of injury woe, look ahead to next month's World Rugby U20 Championship in Manchester where they will face Ireland, Georgia and New Zealand.
Whenever Bedlinog tackle Penallta a massive fixure is guaranteed but this Sunday there will be even more emphasis placed on the two rivals when they contest the SSE Swalec Plate final at Principality Stadium.
Ahead of their SSE SWALEC Bowl Final clash with Taffs Well at Principality Stadium on Sunday, Burry Port share their #FABXV nomination with WRUTV in the search for Welsh rugby's greatest volunteers. Everyone can get involved by sending nominations via twitter to @WRU_Community using the hashtag #FABXV
Cardiff Blues prop Gethin Jenkins and Ospreys centre Ben John look ahead to the first game at Principality Stadium in Saturday's double header which is promising to be a special occasion for all Welsh fans.
Carmarthen Quins Director of Rugby Ian Jones and committee member Jeff Thomas along with Llandovery chairman Handel Davies look ahead to Sunday's SSE SWALEC Cup showdown where both teams are out to prove 'West is best'
SWALEC ambassador Shane WIlliams is looking forward to Sunday's Finals Day where the Cup, Bowl and Plate offers a great opportunity for players and teams to experience the magic of playing at Principality Stadium
Carmarthen Quins coach Richard Kelly believes it is an exciting time to be part of the Scarlets region as his side take on local rivals Llandovery in the SSE Swalec Cup final on Sunday, as WRU TV's Graeme Gillespie discovers