"Everybody is raring to go. It's what we've worked towards all season, so I understand what people say when they ask will Saturday's game define our season.
"We've got a proud history in the Magners League, like Leinster we've won it twice and I guess like them again, we want to be the first team to win it three times. It would be a fantastic reward for the hard work put in by all the squad, coaching staff, and the back office team over the course of the season, but we realise that standing in our way is one of the European giants who have the same ambitions as us.
"We've planned our preparation for the game well, we've broken it up for the boys over the last few weeks and we believe that the 22 going into the game are in pretty good shape.
"We've had two weeks to prepare for this one since the Glasgow game and we've mixed it up a bit, last week the boys were in for a couple of days after a bit of rest, and this week we've stepped it up again but I've got to say they are looking fresh, excited and up for the challenge. Over the last month or so we've been able to build up a bit of momentum and they've got the bit between their teeth."
Shane Jennings will lead the side, with Malcolm O'Kelly lining up alongside Nathan Hines in the second row, in a team which includes 10 Ireland internationals. Jennings continues his back-row partnership with Kevin McLaughlin and Jamie Heaslip.
Meanwhile, Eoin Reddan partners Jonathan Sexton at half-back, with Gordon D'Arcy lining up alongside Brian O'Driscoll at centre.
CJ van der Linde starts in the front row alongside John Fogarty and Stan Wright, while a decision on the replacement prop will be made closer to kick off.
Ospreys 15 Lee Byrne 14 Tommy Bowe 13 Andrew Bishop 12 James Hook 11 Shane Williams 10 Dan Biggar 9 Mike Phillips; 1 Paul James 2 Huw Bennett 3 Adam Jones 4 Alun Wyn Jones 5 Jonathan Thomas 6 Jerry Collins 7 Marty Holah 8 Ryan Jones (Capt)Replacements: 16 Ed Shervington 17 Ryan Bevington 18 Ian Gough 19 Filo Tiatia 20 Jamie Nutbrown 21 Gareth Owen 22 Nikki Walker
Leinster: 15: Rob Kearney 14: Shane Horgan 13: Brian O'Driscoll 12: Gordon D'Arcy 11: Isa Nacewa 10: Jonathan Sexton 9: Eoin Reddan; 1: Stan Wright 2: John Fogarty 3: CJ van der Linde 4: Nathan Hines 5: Malcolm O'Kelly 6: Kevin McLaughlin 7: Shane Jennings (capt) 8: Jamie Heaslip
Replacements: 16: Richardt Strauss 17: Cian Healy / Mike Ross 18: Trevor Hogan 19: Stephen Keogh 20: Paul O'Donohoe 21: Fergus McFadden 22: Girvan Dempsey