Recent signing Miah Nikora will make his first competitive start for Connacht, taking over from Ian Keatley at out-half.
Prop Robbie Morris and centre Niva Ta'auso were not considered because of injury.
Connacht coach Michael Bradley is hoping for a big home support as the province try to bounce back from last week's 62-13 loss in Edinburgh.
"Friday is a big day for us. The more people in, the more pressure we can put on our opponents," he said.
"It's easy to support a winning side - we are not that at the moment - so we are looking for support for the match against Cardiff.
"What we want is consistency. We bounced back last year (after defeats), but we cannot keep doing that.
"This league is tougher than last year with top four places up for grabs, and Cardiff are coming here, having lost to Munster last week.
"That means they have lost their first two matches so if they are going to qualify (for the semi-finals), they will come very strong to the Sportsground.
"We are looking forward to putting last week's result behind us. Last year we went well against them, had a great opportunity to win, but didn't do it."
CONNACHT (v Cardiff Blues): Gavin Duffy; Brian Tuohy, Troy Nathan, Keith Matthews, Fionn Carr; Miah Nikora, Frank Murphy; Brett Wilkinson, Sean Cronin, Jamie Hagan, Andrew Browne, Bernie Upton, John Muldoon (capt), Ray Ofisa, Mike McComish.
Replacements: Adrian Flavin, Ronan Loughney, Mike McCarthy, Johnny O'Connor, Conor O'Loughlin, Ian Keatley, Aidan Wynne.