Alain Rolland (Ireland) will referee the clash of Cardiff Blues and Leicester Tigers at the Millennium Stadium. It will be his fourth tournament semi-final in charge, equaling the record of former Scottish referee and current ERC Board member Jim Fleming.
Meanwhile, French referee Romain Poite will get the big European weekend underway when he referees the match between Northampton Saints and Saracens at Franklin's Gardens on Friday, 1 May with Peter Fitzgibbon (Ireland) in charge at Stade Pierre Rajon for Bourgoin's match against Worcester Warriors.
For the Heineken Cup and European Challenge Cup knock-out games, should the match referee withdraw during the game due to injury he will be replaced by the 4th official.
HEINEKEN CUP 2009 SEMI-FINALS
(Kick-offs LOCAL times)
SATURDAY 2 MAY
17.30 - Munster v Leinster - Croke Park - Nigel Owens (Wales)
4th Official - Wayne Barnes (England)
SUNDAY 3 MAY
15.00 - Cardiff Blues v Leicester Tigers - Millennium Stadium - Alain Rolland (Ireland)
4th Official - Alan Lewis (Ireland)