The task will be more difficult after a spate of injuries has left coach David Young with no option other than to delay a final decision on the starting line-up behind the scrum.
Nick Walne and Shaun James both have shoulder injuries, Rhys Williams has picked up a leg strain training with Wales and Fereti Tuilagi and Jonny Bryant are no longer part of the squad.
Nick Robinson is suffering from a dead leg and is rated as having only a 50-50 chance of being available. Two of the Cardiff Premier Division backs, Chris Czekaj and Dafydd Hewitt, have been added to the squad that will have a run-out on Friday morning.
Young has, however, settled on the forwards' combination. Martin Jones will play at loose-head prop and another Premier Division player, Nathan Llewellyn, will cover him from the replacements' bench.
The backs will be chosen from : Craig Morgan, Dean Dewdney, Tristan Davies, Dafydd Hewitt, Lee Thomas, Jonny Vaughton, Chris Czekaj, Nick Macleod, Nick Robinson, Ryan Powell, Richard Smith.
The forwards are: Martin Jones, Gareth Williams, Ben Evans, Craig Quinnell (captain), Deiniol Jones, Maama Molitika, Kort Schubert, Robin Sowden-Taylor
The forward replacements will be : Nathan Llewellyn, Rhys Thomas, James Goode, Nathan Thomas.
Meanwhile David Young has confirmed that several of the current squad have renewed their Blues' contracts. Along with the earlier announcements concerning Jamie and Nick Robinson, Tom Shanklin, Ryan Powell and John Yapp, new deals have been agree with Kort Schubert, Gareth Williams, Dean Dewdney and Robin Sowden-Taylor.