The Irish province will also face Welsh region Scarlets and English club Exeter in Pool 5.

Last season’s beaten finalists Ulster are in Pool 4 with Northampton, Glasgow and Castres.

Challenge Cup winners Biarritz were drawn in Pool 3 alongside English domestic league champions Harlequins, Irish minnows Connacht and Italian newcomers Zebre.

Pool 1 sees Munster line up with Edinburgh, Saracens and Racing Metro, while four-time champions Toulouse face a tough Pool 2 alongside English giants Leicester and Celtic League champions Ospreys, with Treviso making up the numbers.

Cardiff Blues and Sale will battle it out with French clubs Toulon and Montpellier for top spot in Pool 6.

Only the pool winners and the two best runners-up will progress to the knock-out phase of European club rugby’s showcase tournament.

Draw 

Pool 1: Munster (IRL), Edinburgh (SCO), Saracens (ENG), Racing Metro (FRA) 

Pool 2: Toulouse (FRA), Leicester (ENG), Ospreys (WAL), Treviso (ITA) 

Pool 3: Biarritz (FRA), Harlequins (ENG), Connacht (IRL), Zebre (ITA) 

Pool 4: Northampton (ENG), Ulster (IRL), Glasgow (SCO), Castres (FRA) 

Pool 5: Leinster (IRL), Clermont-Auvergne (FRA), Scarlets (WAL), Exeter (ENG) 

Pool 6: Cardiff Blues (WAL), Toulon (FRA), Sale (ENG), Montpellier (FRA) 

Schedule 

1st round: October 11-14 

2nd rd: October 17-20 

3rd rd: December 6-9 

4th rd: December 13-16 

5th rd: January 10-13, 2013 

6th rd: January 17-20 

Quarter-finals: April 4-7 

Semi-finals: April 26-28 

Final: May 18 at Dublin