The Ospreys will give late fitness tests to Brent Cockbain, Ryan Jones, Alun Wyn Jones and Mike Powell for the potential decider in Swansea.
"It will be a tough turnaround to face Leinster after the Scarlets game," said Ospreys Assistant Coach Sean Holley.
"We have a few injuries, but we're right in there with a shout for the league title and it's our last home game of the season so we will give it our best shot."
The Leinster pack is unchanged from the win over the Dragons last time out, while Chris Whitaker comes in at scrum half in place of Guy Easterby. Leinster are currently top of the Magners League with the third-placed Ospreys - who are yet to lose at home this season - five points behind but with a game in hand.
Ospreys: Stefan Terblanche; Nikki Walker, Sonny Parker, Andrew Bishop, Shane Williams; Shaun Connor, Justin Marshall; Paul James (Capt), Huw Bennett, Adam Jones, Jonathan Thomas, Alun Wyn Jones, Ryan Jones, Richie Pugh, Filo Tiatia
Replacements: Richard Hibbard, Duncan Jones, Mike Powell, Lee Beach, Martin Roberts, James Hook/AN Other, Lee Byrne
Leinster (from): G Dempsey, R Kearney, S Horgan, G D'Arcy, D Hickie, L Fitzgerald, F Contepomi, C Whitaker; R Corrigan, B Blaney, W Green, T Horgan, M O'Kelly, S Keogh, K Gleeson, J Heaslip
Referee: Peter Allan (Scotland)