The Australian Rugby Union is confident its new policy allowing select players to take overseas sabbaticals will help retain talent in the long term, but it is also concerned it could cause some to burn out as they pursue back-to-back seasons without enough rest in between.

ARU chief executive Bill Pulver said he realises player fatigue is a risk of granting select players flexible contracts so long as they commit to Australian rugby on long-term deals.

Asked if he is worried about player burnout, Pulver said: "I am. We are walking a very fine line trying to determine the right policy for the future of the game.

"That policy needs to deliver high performance outcomes on the paddock and as part if that player welfare has got to be a really serious consideration.

"I am also conscious of the fact that dealing with Australian rugby's financial challenges led me to putting more pressure on the players as well.