Head coach Michael Cheika has selected 18 full internationals in a provisional 24-man party for what should be a hugely entertaining clash with the Ospreys at the RDS.
Cheika has named 14 Irish caps including current Ireland skipper Brian O'Driscoll who is one of six British & Irish Lions involved.
Star fly-half Jonathan Sexton is a notable inclusion having missed the Heineken Cup semi-final but returned for the Magners League Play-Off win over Munster.
Club captain Leo Cullen won't be on the pitch on Saturday night, however.
The influential second row has undergone shoulder surgery after missing the 16-6 victory against Munster.
"Leo has gone for an operation on his shoulder and he won't be playing," said Cheika, who is preparing for his final game in charge of the Dubliners before departing for Stade Francais.
"It's hard for Leo because he has battled all season and leads us well. It's disappointing for him, but I think that it was an important decision for him to make; to get that sorted out straight away.
"It was a pretty easy decision to make and it was about getting him right and in the best possible condition going forward."
Cheika also announced that Sean O'Brien will be another absentee despite initially being named in a 25-man squad.
O'Brien hasn't played Magners League rugby since the defeat of the Scarlets back in February but Cheika had hoped he might have recovered from a broken leg in time to make the final.
The Australian has decided that isn't the case, though, and has decided to withdraw the young back rower from the squad, without calling up a replacement.
"Sean O'Brien's not ready yet and he won't be back for this game," added Cheika.
"We decided that after training today and we've got enough in the squad (so we won't be adding to it). The Under-20's have commitments at the moment so we're trying to leave the likes of (Rhys) Ruddock and (Dominic) Ryan out of action if we can. I don't think we'll need to draw on them.
"Cian Healy has been a bit ill and hasn't trained yet since the weekend but, apart from that, everyone's in pretty good nick, bar the standard long-term injuries."
In-form openside Shane Jennings will lead Leinster in Cullen's absence, just as he did against Munster, with Ireland and Lions veteran Malcolm O'Kelly set to deputise for Cullen in the second row.
O'Kelly joins Girvan Dempsey in retiring from the game after Saturday's showpiece, with CJ van der Linde also set to play his last match in Leinster colours.
"Jennings has really come along as far as captaincy is concerned this season and it leaves the door open for Mal to play one more game. I think he showed in the last game that he still has plenty left to give and I'm sure we'll see the best out of him in the last one."
Both Leinster and the Ospreys will named their final matchday squads at approximately 1.45pm on Friday.
Leinster extended squad to face the Ospreys, RDS, Saturday, 6.30pm
Forwards: John Fogarty, Cian Healy, Jamie Heaslip, Nathan Hines, Trevor Hogan, Shane Jennings, Stephen Keogh, Kevin McLaughlin, Sean O'Brien, Malcolm O'Kelly, Mike Ross, Richardt Strauss, CJ van der Linde, Stan Wright
Backs: Shaun Berne, Gordon D'Arcy, Girvan Dempsey, Shane Horgan, Rob Kearney, Fergus McFadden, Isa Nacewa, Paul O'Donohoe, Brian O'Driscoll, Eoin Reddan, Jonathan Sexton
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