Few will be able to look past the defending French champions, considering their star-studded squad and the fact that British & Irish Lions star Leigh Halfpenny is in the matchday 23.
But 31-year-old Heaslip - who has made five Test appearances for the Lions across two tours - has revealed that he and his Leinster teammates are well up for the battle if training is anything to go by.
"When it comes to European games there's always a different feel for training," Heaslip told the Leinster website.
"Lads are very much on edge this week; there's a bit of bite this week in training, which we like - and I definitely like.
"It lets lads know that they're thinking of it, thinking about the game, trying to get the best out of each other and the best out of training.
"There's a good feeling. There's an excited feeling about it, going over there against a team that is made up of superstars - it's like the Real Madrid of rugby.
"The challenge that poses for us is massive and we relish it, and know the work that has to go in in order for us to be in with a chance against these guys."
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