Munster have been left to carry Ireland's hope now that they are the only Irish Province left in the Heineken Cup after Ulster's 27-16 defeat to Saracens at Twickenham last night.
The two time winners take on Harlequins at the Twickenham Stoop in the first of today's quarter finals.
The English Premiership champions start the game as strong favourites with big name players in key positions.
However Rob Penney has Simon Zebo back on the wing for Munster after recovering from a foot injury but there is bad news for Munster as Doug Howlett misses out with a shoulder injury.
Paul O'Connell captains the side today and he says the players believe they can pull off an upset:
Munster's XV vs Harlequins: Felix Jones; Denis Hurley, Casey Laulala, James Downey, Simon Zebo; Ronan O’Gara, Conor Murray; Dave Kilcoyne , Mike Sherry BJ Botha; Donnacha Ryan, Paul O’Connell; Peter O’Mahony, Tommy O’Donnell , James Coughlan.
©INPHO/Russell Cheyne