Leinster, who secured the European title in spectacular fashion at Murrayfield last month, will face a moth watering couple of games against fellow Magners League side The Scarlets, with London Irish and Brive joining them in Pool 6.
There will also be Celtic clashes in Pool 2 and Pool 4 with Glasgow Warriors and Newport Gwent Dragons joined by Biarritz and Gloucester in Pool 2, while Ulster and last season's Magners League runners up Edinburgh meet in Pool 4 - where they are joined by Ulster's old European rivals Stade Francais and Bath Rugby.
Current Manger's League and two-time Heineken Cup champions Munster are in Pool 1 where they face French, Italian and English opposition, while Pool 3 includes The Ospreys and Cardiff Blues are in Pool 5
HEINEKEN CUP 2009/10 POOLS
POOL 1: Munster, Perpignan, Northampton Saints, Benetton Treviso
POOL 2: Biarritz Olympique Pays Basque, Gloucester Rugby, Newport Gwent Dragons, Glasgow Warriors
POOL 3: Leicester Tigers, Ospreys, ASM Clermont Auvergne, Viadana
POOL 4: Bath Rugby, Stade Français Paris, Ulster Rugby, Edinburgh
POOL 5: Toulouse, Cardiff Blues, Sale Sharks, Harlequins
POOL 6: Leinster, London Irish, Scarlets, Brive
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