Foley is currently playing in Japan for the Ricoh Black Rams which is permitted under his current flexible ARU contract and has missed the Waratahs pre-season.
While 26-year-old Foley is expected to re-join the Waratahs next month former Melbourne Rebels fly-half Bryce Hegarty is understood to be the favourite is available to join the Waratahs once his commitments in Japan are complete.
Hegarty has already signed to play for Norths in the Shute Shield competition so he will return to Australia later this year anyway and is familiar with Super Rugby.
The Waratahs announced on Monday that No 8 Wycliff Palu will play for them again this season and his return means that there is just one place left in the squad.
New Waratahs coach Daryl Gibson told FoxSports that he expects to name the new Number 10 next week,.
“Without our two fly-halves, Bernard Foley and another returning from Japan, we’re without a real playmaker there and so we’re filling in at the moment. Once Bernard comes back we’ll be a far more complete side,” Gibson said.
“Given the make-up of our squad we’re really quite short of an understudy to Bernard Foley and we’re looking at a number of options.
“Hopefully that will be named in the next week.
“Internationally, we really want someone who’s just a solid, good all-rounder.”
Another potential candidate is former Waratah Berrick Barnes, who left the side in 2013 and at just 29 years old he could still re-ignite his Test career and add to his 51 Wallabies test caps.
Sam Norton-Knight and former NRL star Craig Wing are also being considered.
The need for a back up 10 comes as Foley played a full Super Rugby season and then went on to the Rugby Championship and the World Cup.
After that he has been playing in Japan so has had little rest time and players who fail to take a break often break down mi-season.
The Japanese season ends almost a month before Super Rugby starts but the Waratahs have a tough pre-season planned and Gibson is concerned about Foley playing back-to-back seasons without a break.
“It’s a concern,” Gibson said.
“Anyone who plays season-to-season will know that it is difficult.
“Certainly it’s something that I’m very mindful of. The fact that he has to go another 12 months of playing, and until he gets back we won’t know what sort of condition he is in and it would be nice to have a luxury where we could actually pull him out of rugby for a little bit.”
In other news Wallabies fullback Israel Folau has had surgery in the off-season on his ankle and will return to running next week and appears to be on track for the opening weekend of Super Rugby.