Ireland forwards coach Simon Easterby says Sean Cronin's omission from the 37-player squad for the France game is due to trying to build depth at hooker.
The Leinster front-row struggled at the line-out during the win over Italy. His omission could be viewed as paying the price for that performance.
But Easterby states that other reasoning is behind the decision to leave him out.
"I think Sean has gone pretty well. There'll be a couple of line-outs that went astray and some of them are strategy. There are so many elements to a line-out. Maybe from the outside, you look at it and go it's a lost line-out," he said.
"But actually when you look at what happens in a line-out, there are so many combinations. You get one of those things wrong - one element of the lift or the jump, the throw, the movement - then it's probably the hooker that gets a little bit of the pressure. So I'd say we've been pretty happy with Sean and what he's produced prior to coming in and while he's been in camp.
"But again, it's about the opportunity to develop some depth in that position. What happened in that Italy game game, I've to hold my hand up, a little bit of strategy that didn't go our way.
"The opposition read a couple and that sometimes is the case. The line-out is complex."
Easterby also reiterated the point about building depth behind Rory Best in the No 2 position.
"It's a specialist position and we need to build depth in it. [Sean] has had a lot of rugby coming into this. He's played really well for Leinster and performed really well with us. We know a lot about him as a person and as a player. We need to know a little bit more about the other guys that we've brought in."
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