SBW stands to earn more money in rugby, but financial pursuits are an ancillary issue to his health as Williams, just turned 28, looks to prolong his career in the 15-a-side code and boxing.
Chiefs management have been told that Williams has enjoyed his NRL stint, but the forward also fears he is being targeted on a weekly basis as the Roosters' headline act.
When he signed with the Roosters, it is believed Williams gave a verbal indication to club supremo Nick Politis that he hoped to back up for a second season at Bondi in 2014.
But discussions around a second year were never formally enshrined in his NRL contract and Politis accepts Williams has a sense of unfinished business in New Zealand rugby.
The former All Blacks forward is keen to play at rugby's 2015 World Cup, while a possible gold medal playing sevens at the Rio Olympics the following year is another carrot.
A New Zealand-based source said: "The Chiefs are very confident of getting Sonny Bill. I expect Sonny Bill to be at the Chiefs [next year] and it will be announced the second the NRL season is over.
"The word out of the Sonny Bill camp is that he is getting bashed in rugby league, he feels he is getting targeted and can look after his body better in rugby union and prolong his career.
"The Chiefs are really close to getting the deal done. With the Roosters in the finals, Sonny Bill wants to keep things low-key until their season is over."
It is understood the Roosters want the NRL to provide scope for Williams' other professional pursuits, meaning any earnings from boxing are not included in the club's salary cap.
"We have put a proposal to the NRL looking at a few specific situations," Roosters chief executive Brian Canavan said.
"What we are looking for is for some flexibility in the salary cap for unique situations and Sonny Bill is a unique situation.
"I accept it must be fair and part of the salary-cap rules that every NRL club can operate by.
"First we need Sonny Bill to say he wants to stay. He is an elite athlete, he has many opportunities available to him, but we'll make an offer when he indicates he wants to stay."
Chiefs chairman Fisher confirmed the province's interest but stressed Williams had yet to formally sign with the New Zealand Rugby Union.
"We are waiting for Sonny to give us an answer on what he wants to do, the ball is entirely in his court," he said.
"Our interest in Sonny is genuine and we are waiting to see how things pan out.
"We are not rushing him, we are waiting for him to get to a point where he will make a decision.
"He's very attractive to us. He is an outstanding athlete with an outstanding profile.
"He will forever be part of the Chiefs and we'd love to have him back."
- Sunday Mail
