Brian Tuohy, Connacht's two-try hero against Glasgow, and flanker Andrew Browne have both recovered from slight knocks to take their places in the side.
The province's replacements bench includes Connacht Academy hooker Dermot Murphy and fit-again centre Keith Matthews.
Connacht have won their last four games in all competitions, including first ever back-to-back wins over Glasgow Warriors last weedend. That victory helped Connacht leapfrog the Scottish outfit in the Magners League table.
Looking forward to Sunday's clash with the defending league champions, Eric Elwood said: "We are going (to Swansea) with the full intention of imposing our game on the Ospreys.
"Yes, it will be difficult because it's a difficult place to go to, and it will be physically demanding, but we are fully committed to winning the game.
"We have eight more games and we are going for it 100%. It is not a case of resting personnel, it is all hands to the pump for the next eight weeks.
"We now know if we play our brand of rugby, maintain possession and have confidence to hold onto the ball, we can ask questions of defences. Conversely, we have to stop defending for long periods of time.
"Against Glasgow we got away with it, but you can't go to the Ospreys and expect to give them all that ball and give away blank. It's not going to happen, so it is an area we have to improve on."
CONNACHT (v Ospreys): Gavin Duffy; Brian Tuohy, Niva Ta'auso, Troy Nathan, Fionn Carr; Ian Keatley, Frank Murphy; Brett Wilkinson, Adrian Flavin, Jamie Hagan, Michael Swift, Mike McCarthy, Andrew Browne, Johnny O'Connor (capt), Ray Ofisa.
Replacements: Dermot Murphy, Ronan Loughney, Rodney Ah You, Bernie Upton, Mike McComish, Cillian Willis, Miah Nikora, Keith Matthews.