League leaders Ulster are home to ninth placed Neath Swansea Ospreys and will start long odd-on to retain their top position. They might even extend their lead because second placed Gwent Dragons are home to third placed Llanelli Scarlets, and that game should yield no more than four points for the winner.
Connacht travel to Scotland for their game with Edinburgh, a side who shipped 50 points at this venue a week ago (v Cardiff).
Munster: (v Leinster Lions). Shaun Payne; John Kelly, Jason Jones-Hughes, Rob Henderson, Mossie Lawlor; Jason Holland, Eoin Reddan.Simon Kerr, James Blaney, Gordon McIlwham; Trevor Hogan, David Pusey; Stephen Keogh, Eddie Halvey, Jim Williams capt. Replacements: (from), Jerry Flannery, Frank Roche, Peter Malone, Tom Hayes, Donal Sheehan, Frank Murphy, Martin McPhail, Conrad O'Sullivan.
Leinster Lions: James Norton; John McWeeney, Christian Warner, David Quinlan, Brendan Burke; Matthew Leek, Brian O'Riordan; Enda Bohan, Gavin HickiePeter Coyle; Aidan Kearney, Ben Gissing; Niall Breslin, Shane Jennings capt, Des Dillon.Replacements: Sean Brophy, David Blaney, Simon Crawford, Ciaran Potts, Shane Whelan, James Downey, Gary Brown
Ulster. (v The Ospreys): Bryn Cunningham; James Topping, Paddy Wallace, Paul Steinmetz, Scott Young; Adam Larkin, Neil Doak; Robbie Kempson, Matt Sexton, Rod Moore; Matt McCullough, Gary Longwell; Andy Ward capt, Neil Best, Roger Wilson Replacements: Paul Shields, Bryan Young, Matt Mustchin, Warren Brosnihan, Kieran Campbell, Sheldon Coulter, Andrew Maxwell
Connacht. (v Edinburgh): Mark McHugh; Matt Mostyn, Darren Yapp, Shane Moore, Conor McPhillips; Eric Elwood, Conor O'Loughlin; Dan McFarland, Bernard Jackman, Adrian Clarke; Damian Browne, Andrew Farley; John Muldoon, Tom Carter, John O'Sullivan. Replacements: Marnus Uijs, Peter Bracken, Mike McCarthy, Paul Neville, Chris Keane, David Hewitt, Ted Robinson.