Match officials to April 29

Europe's elite club competition is down to its final four sides while Super Rugby and the Amlin Challenge Cup are also on this week.

Europe's elite club competition is down to its final four competitors this week while Amlin Challenge Cup and Super Rugby are also on the schedule.

Heineken Cup semi-finals

Ulster vs Edinburgh Rugby at Aviva Stadium, Dublin
Referee: Romain Poite (France)
Assistant referees: Jérôme Garces (France), Pascal Gauzere (France)
Television match official: Giulio De Santis (Italy)

Clermont Auvergne vs Leinster at Stade Chaban-Delmas, Bordeaux
Referee: Wayne Barnes (England)
Assistant referees: Nigel Owens (Wales), Dave Pearson (England)

Amlin Challenge Cup semi-finals

Toulon vs Stade Français at Stade Félix Mayol, Toulon
Referee: Alain Rolland (Ireland)
Assistant referees: John Lacey (Ireland), Dudley Phillips (Ireland)

Biarritz vs Brive at Parc des Sports Aguiléra, Biarritz
Referee: George Clancy (Ireland)
Assistant referees: Greg Garner (England), Simon McDowell (Ireland)

Super Rugby, Week 10

Blues vs Reds in Auckland
Referee: Craig Joubert (South Africa)
Assistant referees: Jonathan Kaplan (South Africa), Glen Jackson (New Zealand)
Television match officials: Ben Skeen (New Zealand)

Lions vs Brumbies in Johannesburg
Referee: Keith Brown (New Zealand)
Assistant referees: Garratt Williamson (New Zealand), Tiaan Jonker (South Africa)
Television match officials: Gerrie Coetzee (South Africa)

Chiefs vs Hurricanes in Hamilton
Referee: Jonathon White (New Zealand)
Television match officials: Glen Jackson (New Zealand), Nick Briant (New Zealand)
Television match officials: Shane McDermott (New Zealand)

Force vs Stormers in Perth
Referee: Jaco Peyper (South Africa)
Assistant referees: James Leckie (Australia) , Damien Mitchelmore (Australia)
Television match officials: Steve Lesczcynski (Australia)

Cheetahs vs Highlanders in Bloemfontein
Referee: Marius Jonker (South Africa)
Assistant referees: Sindile Mayende (South Africa), Stefan Breytenbach (South Africa)
Television match officials: Shaun Veldsman (South Africa)

Waratahs vs Crusaders in Sydney
Referee: Jonathan Kaplan (South Africa)
Assistant referees: Craig Joubert (South Africa), Andrew Lees (Australia)
Television match officials: George Ayoub (Australia)