Pool Three sees Munster, Ospreys, London Irish and Toulon slug it out for a place in the knockout stages.
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Pool Three sees Munster, Ospreys, London Irish and Toulon slug it out for a place in the knockout stages.
Munster
The two-time champions love the European stage but they know they will have to lift their performances if they are to repeat their 2008 heroics.
They have won 77 of 109 Heineken Cup matches since 1995 - playing in the last four for the past three seasons.
They currently top the standings in the Magners League, although they were edged out by Leinster last time out.
That blip aside, they have a side oozing class and experience - including the unstoppable points scoring of Ronan O'Gara, who has scored 1,138 points in 91 Heineken Cup appearances.
Ospreys
The Magners League champions have their sights set on becoming the first Welsh champions of the Heineken Cup.
They have reached the quarter-finals for the past three seasons - but they could find life harder this time around.
A 22-10 defeat to Munster at Thomond Park earlier in the season highlights the work that needs to be done if they are to be considered serious contenders.
They have the talent, though, to rise to the big occasions with the likes of James Hook, Tommy Bowe and Ryan Jones.
London Irish
The Exiles will take part in only their fifth Heineken Cup - and they will be looking to at least emulate their exploits from the 2007/8 season.
Irish swept aside the likes of Treviso, Newport-Gwent Dragons and Perpignan as they reached the last four - only for Toulouse to end their run.
Toby Booth's side go into the competition buoyed by a return to the form that took them to those dizzy heights, and they currently top the Aviva Premiership.
The club's strength-in-depth may become an issue as the competition goes on but in Ryan Lamb, Topsy Ojo and Delon Armitage they have some exciting backs.
Toulon
Still stinging after finishing last season trophy-less, big-spending Toulon are determined to add silverware this time around.
They lost out to the Blues in the final of the Amlin Challenge Cup, but they at least showed they are comfortable on the European stage - with victories over Connacht, Scarlets, Castres and Saracens.
They kick-off their debut in the Heineken Cup fresh from an encouraging run of domestic form.
Jonny Wilkinson remains the heartbeat of the Toulon side - but there is a wealth of international talent available to boss Philippe Saint-Andre.
