Joe Schmidt remains in the dark about which of his Irish internationals he will have available when Edinburgh visit Dublin on Saturday.
The Leinster coach admitted yesterday that the momentum built up in the last number of weeks has been checked by the departure of squad members to Limerick ahead of the November Tests.
And the New Zealander has warned that the best any player released late in the week can hope for is a spot on the bench for the important Magners League fixture.
"At the moment, we've got 13 guys involved (with Ireland)," Schmidt said. "We're not sure who's coming back, which makes preparation for this weekend relatively difficult.
"I think there's a couple we can maybe guess at, but it's crazy to get because we're not absolutely sure. Some of them, they might want to give more game time to. Jonny Sexton has only had three games, so is that enough to have him in top shape? I'm not sure.
"There are other guys, like Luke Fitzgerald, who took a bit of a knock but could have played for us last week. I don't know really what their thoughts are, as far as those kind of guys are concerned.
"Initially, we heard (the players would return on) Tuesday night, so (we would have them) from Wednesday onwards, but we're not sure again.
"There's an indication there may be some guys coming back at the end of the week. If that is the case, all we can do is put them in the reserves because you just can't have a training week without the playing staff there."
Having won just one of their opening four matches -- culminating in a dreadful away defeat to this week's visitors -- Leinster lie sixth in the league table despite their recent resurgence. And Schmidt says they need to build their points tally despite their international absentees.
"We're in a tenuous position, there's no doubt about that," he said. "It's not just because it's Edinburgh. We have the Dragons coming up, then after that, if that doesn't go well for us, we're again battling off the bottom third of the table, which means we've given everyone a head start.
"The fact that it's Edinburgh means they've got all their Scotland players available. I think even some of the Welsh teams don't have everyone available so it would have been nice to have drawn anyone but a Scottish side this weekend. But we can't change the draw.
"We'll have tough Heineken Cup games coming up, plus we'll have to rest guys over the two Christmas weekend games. We will tend to fluctuate and with that fluctuation comes the pressure of slipping up and down the table -- but not up it consistently."
With the front-liners sidelined, Schmidt is expected to delve into Leinster's reserves to bolster his side and he wants the youngsters to take their opportunity.
"They've been working really hard and they deserve to get this opportunity. And at the same time, they have a responsibility to make the most of that opportunity."