So much of what Ireland will achieve this season will revolve around the presence of Brian O'Driscoll, Paul O'Connell and Jonathan Sexton; or, lack of it.
Ireland coach Joe Schmidt seemed to have confidence that O'Driscoll has shaken off the discomfort from his Grade-1 calf tear and will be able to play against Samoa tomorrow week.
"The one thing I would say about Brian is he is training really well. He is looking sharp. He is pretty comfortable on the pitch at the moment," he said.
"I have no doubt a steely mind can overcome fatigued lungs and, at this stage, I'd be really comfortable with Brian starting against Samoa if that's what we think is the best option."
There is a distinct possibility that Sexton, who flew back to Paris last night because Racing Metro play Biarritz in the Top 14 tomorrow, will miss out on the first international of the season given how he has played so much rugby already.
Apparently, it is a simple equation; if Sexton plays for his club against Biarritz, the chance of him turning out against Samoa is slim.
"Any decision we do make will be in discussion with Jonny," said Schmidt.
Schmidt was waiting on a phone call from Racing coach Laurent Labit for further information about Sexton's involvement.
"One of the things, unfortunately, is that they own Jonny's services and they're fully entitled to make use of them, because they are pretty good services to have.
"He does have an eight-day period post the November series to have a rest, so if he's feeling right up to it and he feels he can take on the three-match series and maintain a level of performance, fitness and enthusiasm through that period, then we would certainly look at that.
"He's a pretty buoyant character, and a pretty bossy character, in a really good sense, because he gives great direction on the field. And he was definitely a bit flat at the start of the week," he said.
"It's one of those things that does make things pretty difficult. It's another uncontrollable; there are enough uncontrollables in rugby without adding to them.
"I'm hopeful that Johnny will get the weekend off, whether it's in Ireland or in France, and then that will freshen him up.
"Having played 13 games in 12 weeks, you know a player will start to get a bit of fatigue. You just become a little bit more vulnerable, a little less likely to avoid injury. Those are risks we want to manage.
"If Johnny is run down next week and he does play at the weekend against Biarritz, it's a great opportunity for Paddy (Jackson) or Ian (Madigan) to step up and try and make a mark."
Schmidt found it "impossible to say" whether O'Connell will overcome his Grade-1 calf tear, leaving next Tuesday as the cut-off point for the Munster man.
"He is very much abreast of what we're doing. He has been out on the pitch for all the sessions. He is the sort of guy who does his homework pretty well."
There must be a strong temptation for Schmidt to throw O'Connell into battle against the super-physical Samoans tomorrow week.
"Yeah, that's something you've just got to balance and weigh up and I'll be guided by the medical staff, to be honest.
"There's quiet optimism among the medical staff that Tuesday wouldn't be unrealistic for Paul, if he can get out on to the pitch on Monday and start doing some straight-line sub-maximum stuff."
There was better, more hopeful news about two other British and Irish Lions in Cian Healy and Seán O'Brien. They are scheduled to be back training by Monday, or Tuesday at the latest.
The issue of the captaincy is still there to be decided. Will Jamie Heaslip hold on? Is Schmidt waiting for O'Connell to be passed fit? What about Sexton or Rob Kearney?
"To be honest, the captaincy is still a bit of a moot point," said Schmidt.
"The guys who are showing leadership are mixed across the board and, as a result, we're pretty comfortable with where we are at the moment and probably the earliest we would name a captain is prior to the team announcement next week, maybe Tuesday or maybe Thursday."
Even then, the choice may not be definitive for the Six Nations as the office of the captain may not be a permanent one, depending on a number of issues, yet to be concluded.
"It's impossible to answer that because it may depend on who, in the end, is available and what we think is the best mix. With Les (Kiss) and John Plumtree we've put our heads together a few times and just tried to work out who are the leaders."