England backs coach Andy Farrell believes allowing full-back Mike Brown another week's recuperation "was the right and proper thing to do".
Farrell will preside over a new-look back three for the remainder of this week, but is convinced both Alex Goode and Jack Nowell will shine on Sunday.
Brown woke up this morning with a mild headache and thus failed to progress in his return to play protocol following a head knock against Italy.
And Farrell has explained the decision and how it would affect the matchday squad, citing the Harlequin's consistency over the past two seasons.
"[Brown] woke up feeling not 100 per cent," he said.
"It was the right and proper thing to do for us to make the call. Getting himself right for the next game is the main priority.
"The symptoms were not too severe whatsoever – he just had a bit of a headache. He's fine within himself, chirpy enough, but it just isn't worth the risk. His health comes first.
"We're missing an experienced player in fantastic form who stands up in pressure situations and performs extremely well. With the young backline we've got, he has been a massive help for us."
Goode is set to wear the number fifteen jersey this week while Jack Nowell will be on the wing, with Farrell excited to see how they play.
"Alex, coming in, is an experienced guy himself who has been waiting for his chance. His form for Saracens in the big games against Munster and Clermont has been exceptional.
"He's super excited. All you ask from a player waiting in the wings is form them to be ready. He certainly is.
"Jack was having an awful time with injury six months ago and he's been biding his time. It's only the last month or so he's been able to train properly with us.
"Week-in, week-out he has been dangerous in all areas of his game for Exeter. The time is right for him."
And on the upcoming game in Dublin, Farrell admits the excitement is building in the England camp.
"Every game is big in the Six Nations – it's a fantastic competition. It's third in the log and we’ve both started reasonably well.
"There's a lot of hype around the game, a lot of tension as well. But these are two teams that are very focussed and it will be a cracker come Sunday.
"We know Ireland will be at their best. They have experienced players who will get them to that level.
"What we were very good at in Wales was reading the game as we went, feeling the momentum swings and acting on them.
"We kept our composure then and we'll have to do exactly the same this weekend."