Leinster have brought out the big guns for the opening salvo of the double-header.
The visitors are 1/8 favourites in some places and Bath would have to pull something special out of the bag to overturn the reigning champions.
Leo Cullen admits that the presence of former Leinster man Girvan Dempsey at Bath is a "danger" but more telling is what the head coach said after that: "Sometimes, even if teams know what's coming, they still have to be able to handle it."
When it comes to this Leinster side, there's never been a truer word spoken.
Bath out-half Freddie Burns suffered a foot injury in training so misses a chance to face the World Rugby Player of the Year in Johnny Sexton.
On the plus side, Todd Blackadder welcomes back Tom Dunn, Dave Attwood and Jamie Roberts, who were rested last weekend.
Expect Leinster to bounce back from a rare European defeat in style.
Joe Schmidt will probably be keeping an eye on this one.
Not least for the fact that Conor Murray and Joey Carbery will form the Munster half-back partnership for the first time since the latter's high-profile move from Leinster over the summer. They have played together for the national side.
Speaking during his injury lay-off, Murray said: "Joey has settled in really well."
Now the pair will get the chance to give the Thomond faithful a glimpse of what's possible.
The current Top14 champions had a narrow home win over Exeter and lost to Gloucester. Munster are top of the pool after a win and a draw.
You'd almost feel sorry for Perpignan: rock bottom of the Top 14 table, 12 defeats and a draw from 13 games in total, no Paddy Jackson in their ranks. And the weather outside is frightful.
It looks like it's going to be a wet day at the Sportsground and to cap it off, Bundee Aki has decided to stick around for this game having initially been granted leave to get married back home in New Zealand.
The Westerners come in off the back off a two-win trip to South Africa.
"It's really important that we build on that Cheetahs performance," said Connacht boss Andy Friend
"You can see out game is building but we haven't clicked yet. We don't want to be the team that gives them [the win]".
Connacht are second in Pool 3 after a loss to Sale and a win over Bordeaux.