The Blues make four changes from the side beaten by the Ospreys last weekend with Nick MacLeod and Dean Dewdney forming a new half back partnership while Nick Walne and Nathan Thomas also return.
Michael Bradley has used his rotation policy to maker five changes to the Connacht side Mark McHugh making his first start of the season, and John O'Sullivan returning from injury.
Blues team: Rhys Williams; Nick Walne, Tom Shanklin, Tristan Davies, Craig Morgan; Nick Macleod, Dean Dewdney; Gethin Jenkins, Gareth Williams, Martin Jones, Deiniol Jones, Robert Sidoli, Nathan Thomas, Kort Schubert, Martyn Williams (Capt)
Replacements: Ken Fourie, Andrew Lewis, Heino Senekal, Robin Sowden-Taylor, Richard Smith, Lee Thomas, Jonny Vaughton
Connacht team: David Slemen; Niall O'Brien, Matt Mostyn, Mark McHugh, Conor McPhillips; Paul Warwick, Tom Tierney; Dan McFarland, Bernard Jackman, Peter Bracken; Pieter Myburgh, Andrew Farley; Paul Neville, Matt Lacey,John O'Sullivan
Replacements: John Fogarty, Adrian Clarke, Michael Carroll, Michael Swift,Eric Elwood, Conor O'Loughlin, Ted Robinson