The GUINNESS PRO12 outfit are chasing a double over their English counterparts, while defeat would leave their hopes of a European quarter-final in the dust.
Foley is keeping his fingers that Ireland scrum-half Murray will recover in time from a neck injury he sustained in last weekend's GUINNESS PRO12 trip to Zebre.
"He didn't train today (Tuesday) - he took part in some organisational stuff but didn't train," he told the Limerick Leader.
"We're getting the scan read, we'll know later. We need to make sure he's functional."
Meanwhile, there are also question marks over winger Keith Earls and prop James Cronin, who each made their return from injury off the bench in Parma.
And Foley admits he will need as many weapons at his disposal as possible, with a premature exit from the competition looming over their heads.
He added: "What you have to look at is what the weekend took out of them.
"They obviously trained today fully and we need to see how they rock up tomorrow (Wednesday) so we can make an assessment on them.
"If we lose we are basically out, we understand that and we need to go about our job as if we are playing a knock-out game.
"The same as if you have any sense of imagination when we were young fellas playing schools cup matches 'this is it, there is no tomorrow'."
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