O’Driscoll will be making his first appearance for the province after making significant progress in recent weeks following injury and he will partner fellow Ireland international Fergus McFadden at centre for the visit of the Welsh side.
World Cup winner Thorn will make his debut after signing a short-term deal with the province.
Ospreys Head Coach, Steve Tandy, commented: “It’s good to be able to welcome back our internationals on the back of their Grand Slam success, and we’ll be looking for them to bring that buzz back with them to the region.
“We’re proud of what they’ve achieved with Wales, to have 11 boys involved in the Grand Slam is something special, but it’s important now that everyone focuses on the remaining five games of the regular season and the battle for the play-offs.
“Leinster away is always a big ask. Their home record in this competition speaks for itself so we know what to expect out there. But, we’ve won there before and there are plenty of players in this group with that experience to fall back on so although we are still a pretty young group, we believe in each other and our own ability.
“After a disappointing performance last time out it’s important that we show the right attitude. It’s really tight in and around the play-off spots and things are likely to change after every weekend now, so we just have to go out and do what we need to do and not worry about anything else.
“After Leinster we’ve got Treviso home, and the first chance for our fans to come out in numbers to acknowledge the Grand Slam success and a fantastic Osprey in Adam Jones on his first game at the Liberty since signing a new two-year contract last month, so we’ll expect a good crowd turning out to back us.
“The reality of the situation is we’ll need to be entirely focussed again, as we will every game, know our roles, get our jobs right and ensure we keep moving towards a semi-final place. The fans will have a part to play in that in the closing weeks of the season, giving us the backing we need to get over the line.”
Leinster: 15: Isa Nacewa 14: David Kearney 13: Brian O’Driscoll 12: Fergus McFadden 11: Luke Fitzgerald 10: Ian Madigan 9: Isaac Boss; 1: Heinke van der Merwe 2: Richardt Strauss 3: Nathan White 4: Leo Cullen (Capt) 5: Brad Thorn 6: Rhys Ruddock 7: Dominic Ryan 8: Leo Auva’a.
Replacements: 16: Sean Cronin 17: Jack McGrath 18: Jamie Hagan 19: Damian Browne 20: Kevin McLaughlin 21: John Cooney 22: Eoin O’Malley 23: Fionn Carr.
Ospreys 15 Richard Fussell 14 Hanno Dirksen 13 Andrew Bishop 12 Ashley Beck 11 Eli Walker 10 Dan Biggar 9 Kahn Fotuali’i; 1 Paul James 2 Richard Hibbard 3 Aaron Jarvis 4 Ryan Jones 5 Alun Wyn Jones (Capt) 6 Tom Smith 7 Justin Tipuric 8 George Stowers
Replacements: 16 Scott Baldwin 17 Ryan Bevington 18 Adam Jones 19 Ian Evans 20 James King 21 Rhys Webb 22 Matthew Morgan 23 Tom Isaacs
