Joe Schmidt has revealed the impact a move to France had on Jonathan Sexton influenced his decision to drop Simon Zebo from the Ireland squad.
Zebo was last week snubbed for the November internationals after opting to leave Munster and head to Racing 92 at the end of the season.
Schmidt said the Irish Rugby Football Union (IRFU) have not adopted a stance of overlooking overseas-based players, but pointed to former Racing fly-half Sexton as proof that playing abroad can have a negative impact in the long term.
"There is no policy, there is only an intention from the IRFU to best protect the provinces and the local game," said the Ireland head coach.
"We believe that the best way to do that is to select from within Ireland.
"There's one player [Sexton] who went to Racing and was played for the first 12 games in the season, and I'm not sure he's ever had the same resilience since then.
"I think it's pretty self-evident - Johnny [Sexton] hasn't played 12 games in a row since then and that's because you pick up the wear and tear and it's hard then to get that back. We're looking to add to the longevity of our players."
Schmidt said the versatile Zebo's switch to the Top 14 opens the door for other players to make their mark on the international stage, but did not rule out the Paris-bound flyer returning to the fold down the line.
He added: "Simon signing for Racing is an opportunity for us. Simon's had 35 Test matches, we know a lot about Simon.
"What we have done is try to back ourselves to keep people in the country. We've got 19 Test matches before the build-up to the World Cup. This is an opportunity for some of the other players.
"It's not a done deal as far as somebody not being able to play for Ireland from outside the country, but... no one is ruled out."