Coach Michael Bradley hopes to finalise his team on Thursday morning.
Commenting on last week's heavy defeat to Edinburgh, the former Ireland scrum half said: "The performance in Edinburgh was unacceptable. It was an embarrassing result and we need to respond quickly to it.
"We have been working hard all week to eliminate the errors from our play."
Bradley has been emphasising the importance of display to his players - the westerners have worryingly had four players sin-binned in their opening two games.
"We do not want to experience being down to 13 men again. If we continue to hand an advantage to the opposition we will be punished.
"The DVD of the Edinburgh match made for some very unpleasant viewing. Hopefully the crowd will get behind us this weekend and lead us to a good result."
CONNACHT Squad (v Cardiff Blues): Backs (10) - Fionn Carr, Gavin Duffy, Ian Keatley, Keith Matthews, Frank Murphy, Troy Nathan, Miah Nikora, Conor O'Loughlin, Brian Tuohy, Aidan Wynne.
Forwards (14) - Andrew Browne, Sean Cronin, Adrian Flavin, Jamie Hagan, Conor Higgins, Ronan Loughney, Mike McCarthy, Mike McComish, Robbie Morris, John Muldoon, Johnny O'Connor, Ray Ofisa, Bernie Upton, Brett Wilkinson.