Irish duo Donal Courtney and Alan Lewis will be the men in the middle for the Parker Pen Challenge Cup semi-final home and away legs between last season's runners-up Bath Rugby and the 1999 champions Montferrand.
Courtney will control the first leg at The Recreation Ground on Saturday, 10 April (kick-off 1.00pm local time) and then Lewis will be in charge at Parc des Sports Marcel Michelin two weeks later on Saturday, 24 April (kick-off 2.00pm local time).
The other Challenge Cup semi-final, between 2001 champions NEC Harlequins and Connacht, will have a mix of Italian and Welsh officials.
The highly experienced Italian Giulio de Santis will take charge of the first leg at The Stoop on Sunday, 11 April (kick-off 1.00pm local time), while Wales' Nigel Whitehouse will be in control the return leg in Galway on Sunday, 25 April (kick-off 1.00pm local time).
PARKER PEN CHALLENGE CUP SEMI-FINAL REFEREES
(All kick-of times LOCAL times)
SATURDAY, 10 April - Kick-Off 1.00pm
Bath Rugby v Montferrand - Donal Courtney
(Ireland) Sky / Sport +
SUNDAY, 11 April - Kick-Off 1.00pm
NEC Harlequins v Connacht - Giulio de Santis (Italy)
Finals Edition: Listen to the best guide to the European Rugby Cup Finals weekend in Dublin, which sees Leinster Rugby take on Stade Francais Paris at the RDS on Friday night in the Amlin Challenge Cup Final and then ASM Clermont Auvergne tackle Toulon in an all-French affair at the Aviva Stadium on Saturday.