McCall's champions facing a difficult ask
Holders Saracens have been dealt a tough pool in defence of their Heineken Champions Cup crown next season.
Ulsterman Mark McCall's European and Premiership title holders were drawn in the same group as Munster - the team they beat in last season's semi-finals - Racing 92 and Ospreys.
The blue riband European tournament also sees Premiership runners-up Exeter grouped with Glasgow - their new star signing Stuart Hogg's former club - Sale Sharks and La Rochelle.
Danny Cipriani's Gloucester, meanwhile, were pooled alongside French champions Toulouse, Connacht and Montpellier.
Premiership rivals Bath and Harlequins will contest Pool Three with Clermont Auvergne and Ulster, and four-time European champions Leinster are joined in Pool One by Northampton, Lyon and Benetton.
Leicester will face Cardiff Blues, Pau and Calvisano as their pool stage opponents in next season's European Challenge Cup.
Elsewhere, Leicester's fellow former European champions Wasps were grouped with Edinburgh, Bordeaux-Begles and Agen, while newly-promoted Premiership club London Irish will tackle a testing pool against Scarlets, Toulon and Bayonne.
New Dragons boss Dean Ryan will face an appointment with one of his former clubs Worcester in Pool One, and Pool Four sees Bristol facing French threats from Stade Francais and Brive.
The group stages of both tournaments begin in mid-November, two weeks after the Rugby World Cup final.
Reflecting on Exeter's draw, rugby director Rob Baxter said: "It was almost destined that with us having signed Stuart from Glasgow that he would end up facing them in Europe.
"Having played Glasgow in the past, we know they will pose a tough challenge. They have a team packed with Scottish internationals and are a team, a bit like ourselves, who like to attack.
"As for La Rochelle, it's been a few years since we faced them in the Challenge Cup.
"Again, they will be a different beast to what they were back then. As for Sale, every year you always know going up there is one of your toughest away days."