HOOKER Rory Best is the spearhead of the Irish scrum and the deadeye dart player at the oche, which is the sideline to their lineout. He has to be aggressive and accurate.
He has to master the twin challenges of the power and technique of working in unison with his props at the scrum and the finesse, timing and accuracy to find his men in the air at the lineout.
The Ulsterman received one blow and one boost from the announcement of the France team to play Ireland in the Six Nations at the Stade de France on Sunday.
Best will not have to deal with the brutish scrummaging of hooker William Servat from the start -- he is on the bench -- but Julien Bonnaire has been drafted into the back row.
This is as intimidating as it gets for any international thrower. France coach Philippe Saint-Andre has paired Pascal Pape and Yoann Maestri at lock, with Bonnaire and the dastardly Imanol Harinordoquy beside captain Thierry Dusautoir in the back row.
"There's no doubt even in terms of international rugby that Bonnaire and Harinordoquy are two of the best operators there are," said Best.
"They have made that change and it is a good challenge for us. We know we are going to have to be on our game at the lineout."
France will not be content to test Ireland in the air. They made a point out of opting for scrums from indirect penalties and leaving the ball in long enough to force Scotland to give away penalties or to give ground.
Former France hooker Yannick Bru is their forwards coach. He has already put his stamp on the new regime. Props Nicolas Mas and Jean-Baptiste Poux must be enjoying it.
The review of what went wrong is part of every player's preparation and Ireland will have to improve out of touch to keep in touch with World Cup finalists France.
Best isn't sure whether it has turned out for the better to travel to France with a win under their belt rather than the defeat administered by Wales.
"We had the added advantage of trying to settle a score from the Wales game, which was always going to be a motivating factor," Best said.
"Now, to come off the back of a good win, we scored five tries against an Italian team which doesn't concede 40 points to many in international rugby these days.
"It is very encouraging to go to France with that behind us. We are a few more weeks together and we are starting to iron out the wrinkles."
However, it is the wrinkles that have aged Ireland's players and supporters from their deplorable experiences in Paris over the years that make for the most concern.