Joe Schmidt is confident Johnny Sexton and Sean O'Brien will be fit for Ireland's Six Nations opener against Scotland on February 4.
Fly-half Sexton suffered a calf injury while playing for Leinster in their 24-24 Champions Cup draw at Castres on Friday while back-rower O'Brien has been battling a similar problem.
But Schmidt is not anticipating being without either player when Ireland begin their campaign at Murrayfield in the first weekend of February.
Schmidt named only two specialist fly-halves in his squad on Monday - Sexton and Paddy Jackson - and confirmed on Wednesday that Munster centre Rory Scannell would provide cover at No 10 if necessary.
"Johnny took a bruised calf in to the game against Castres and it just tightened up," said Schmidt.
"There's not a lot of damage there, nothing's showing up that's overly significant. Johnny's already starting back doing a little bit.
"We'd be confident he'll be able to train next week and therefore be fully available to face Scotland."
"Sean is slightly further ahead than Johnny. We're confident he may train before the end of the week fully, but he should train fully next week."
Schmidt is not ruling out a call for Ian Madigan later in the tournament after the Bordeaux player missed out on his original selection.
But he is happy with the back-up Scannell can provide at the moment, even if fly-half is not his preferred slot.
"The first time I saw Rory play for Dolphin against Belvedere he had a fantastic game at 10," said Schmidt.
"There's a big difference between that and Murrayfield but he would be the guy who could cover there.
"We've also got Paddy Jackson available obviously. With Ian [Madigan], he could only have done those two first days with us.
"You only get that three-day opportunity with the window. So it complicates that. Ian had an injury earlier in the season so he hasn't had a lot of rugby really.
"I've kept in touch with Ian. He would slot back in pretty seamlessly for us, so that's still something potentially that we could look at."