Pool 1: Glasgow, Leicester, Munster, Racing 92

The group of death, Pool 1 contains former European champions Leicester and Munster, last season’s runners-up Racing 92, as well as Gregor Townsend’s exciting Glasgow side. Richard Cockerill’s men will be out for revenge following last season’s semi-final defeat to the French side and with some noteworthy additions in the shape of World Cup-winning Springbok JP Pietersen and Australian Matt Toomua to what was already a deadly-looking backline, expect the Tigers to go toe-to-toe with Dan Carter’s Racing side who themselves will be looking to go one better following a disappointing showing in the final against Saracens last season. Munster’s European pedigree means they can never be written off especially at home, but the biggest challenge to Leicester and Racing will most likely come from a Glasgow side who beat Munster to secure a maiden Pro 12 title in 2015. With a number of key Scottish internationals such as Jonny Gray, Tommy Seymour and Stuart Hogg in the Glasgow ranks, Townsend’s side are known for their exciting brand of rugby and whilst away trips to Leicester and Racing may leave the Scottish side up against it to qualify from the Pool, they will prove a tough nut to crack at home.

Pool 2: Connacht, Toulouse, Wasps, Zebre

One of the easier groups to call, Dai Young’s Wasps side have started from where they left off last season winning five of their opening six Premiership matches, and will fancy their chances of maintaining that solid form in this Pool. With a raft of impressive new signings such as Danny Cipriani, Kurtley Beale and Willie La Roux, the Coventry-based side will look to improve on their semi-final showing from last season and have the talent to go potentially all the way. French giants Toulouse may well have something to say about that but like Munster despite their great history in Europe they are no longer the dominant force they once were, although qualification via a best runners-up spot may not be out of the question. Reigning Pro 12 champions Connacht’s early season form may have left them languishing in the domestic league, but Pat Lam’s side will be eager to make the most of their return to the Champions Cup and whilst unlikely to challenge for qualification, will fancy their chances of taking down Toulouse in Galway. A tough-looking task for Zebre who will once again be playing for pride.

Pool 3: Toulon, Sale, Scarlets, Saracens

The Clash of the Titans as defending champions Saracens meet former champions Toulon in a group which will most likely see both sides progress to the knockout stages. Having won three consecutive European titles from 2013 to 2015, Toulon will be desperate to make amends this season after surrendering their title at the quarter-final stage last time around. A star-studded line-up containing a sizeable number of internationals including Ma’a Nonu, Bryan Habana and Leigh Halfpenny, the French giants will once again be one of the favourites to go all the way this year. However in their way lie the defending champions and favourites Saracens. Having started the defence of their Premiership crown with five wins out of six, Mark McCall’s men will begin the defence of their European crown with a trip to the South of France, as they look to maintain an incredible winning sequence that saw them go unbeaten throughout their Champions Cup campaign last season. Having lost in the final to the French side in 2014, Brad Barritt’s side will be out for revenge when they meet this weekend, but regardless of the result expect these two to make it through, with the only question seeming to be who finishes on top. For Sale and Scarlets the signs are ominous and while both will look to cause upsets against the big guns, these two will probably be battling it out for 3rd place.

Pool 4: Castres, Leinster, Montpellier, Northampton

A very competitive-looking group which looks hard to predict from the outset. After winning three European titles in four seasons not so long ago, Irish side Leinster have fallen off the wagon the last few years being overtaken by the likes of Toulon and Saracens as the dominant force in European rugby. Saying that a squad containing world-class talent in the shape of Jonny Sexton, Jamie Heaslip and Sean O’Brien should not be written off and with promising Ireland centre Robbie Henshaw joining in the summer from Connacht, coach Leo Cullen will be looking for his side to make their mark in Europe once again. The Irishmen will most likely be vying for top spot with Challenge Cup holders Montpellier and Jim Mallinder’s Northampton Saints side. Lying in 3rd place in the Top 14 and with South Africa’s World Cup-winning coach Jake White in tow, the French side look very well-prepared for the step up in class, especially with Springboks Bismarck du Plessis and Pierre Spies in their ranks along with new signing Nemani Nadolo. For Northampton, Europe will provide a welcome break from a mixed start to the Premeirship, and having sneaked through to the knockout stages after a poor start last time around they too can not be written off. Castres will look to take advantage of home form to sneak a few wins but having started the season poorly they will struggle to progress to the knockout rounds.

Pool 5: Clermont, Bordeaux, Exeter, Ulster

Another very tough group to call, with a number of sides who could potentially go far in the competition. With Exeter having qualified ahead of both Bordeaux and Clermont by the tightest of margins in last season’s pool stages, old friends will meet again in this group, as the three sides meet at this stage for the second campaign running. Losing finalists in 2013 and 2015, Clermont will be looking to avenge their surprisingly early exit from the competition last year, when Bordeaux’s shock win at the Stade Marcel-Michelin saw the Chiefs leapfrog Clermont to secure a quarter-final berth. Bordeaux themselves will be desperate to qualify having just missed out on a quarter-final spot last season, despite finishing on the same points as Exeter. With all that in mind expect home form to be crucial once again between these sides. Pro12 high-flyers Ulster will also have something to say about qualification in this Pool with world-class backs Ruan Pienaar and Charles Piutau running the show. On paper, the tightest group to call with all four sides capable of beating the other, bonus points may well be the difference.