Leinster coach Leo Cullen must plan without Seán O'Brien, Richard Strauss, Mike McCarthy and now Jack Conan for Saturday's trip to Bath in round two of the Champions Cup.

The injury problems, enhanced by the triple concussions they suffered during last Sunday’s record 33-6 home defeat to Wasps, have been exacerbated by Conan breaking a bone in his foot, an injury that will require six to 10 weeks of recovery.

Rhys Ruddock is fit to start while Josh van der Flier has not been included in Friday's A squad to play Moseley.

With the pack severely under-strength, Cullen remains hopeful that Ben Te'o, Rob Kearney, Luke Fitzgerald and Isa Nacewa can recover from recent problems to bring some form of cutting edge to the backline.

“I find every week tough,” said Cullen when asked about preparations.

“There is never enough time to do what you want to do. I was under no illusions coming into this job that there as going to be some tough days.

“The scoreline, 33-6, I don’t think paints a true reflection of what happened in the game, but unfortunately there is no getting away from 33-6. It’s the reality at the end of the day. We had 63 per cent possession, Wasps had zero breakdowns in our 22 yet they managed to come away with 33 points.”

Regarding those completing return to play protocols, Strauss must be a major concern as he has been forced off on at least three occasions in the past 12 months due to head traumas.

“(Richardt) has a history of a couple of head knocks but he was up and about fine after the game. But with that history we tend to err of the side of caution.”

Defeat will almost certainly end their chances of qualifying before back to back December games against three-time champions Toulon.

"I don't think it's a World Cup hangover," said Devin Toner of the Wasps game. "It was just a bad day."