Despite amassing 30 games in all competitions for the club which shook up the Chinese Super League by finishing runner-up to powerhouse Guangzhou Evergrande, as well as reaching the domestic cup final, the centre-back is taking nothing for granted in the crazy world of Chinese football.
In camp with the Socceroos preparing for Tuesday's 2018 FIFA World Cup qualifier against Thailand in Bangkok, Sainsbury declared: "I have two years left after this season and there's the security of the contract there.
"But China is a revolving door, with players coming in and out, so we will see what happens at the end of the year.
"I am not sure if I will be here or not beyond this season, that's up to the club to decide.
"It's alway exciting in football ... you never know where you are going to be next, so we will just wait and see."
Though he's flourished in a line-up laden with big money acquisitions like $65 million Brazilian magician Alex Teixeira and his compatriot Ramires, Sainsbury is all too aware of China's reputation as one of football's most volatile marketplaces.
"Nothing really surprises me anymore in football," he said. "You see players doing really well at one club and the next minute the club wants you out the door.
"It happened to Timmy (Tim Cahill) at Shanghai Shenhua. He was doing really well, he was their second top scorer and they just got rid of him.
"You just don't know any more these days ... football's a business. People want the best results and if they think they can buy someone better then they will do it."
While happy in China, Sainsbury, who dreams of one day playing in the Premier League, is ready for any eventuality.
"I am enjoying myself here ... life in Nanjing is pretty easy for me now because we are pretty used to it but at the same time me and my partner are always looking for new adventures and you have to try and enjoy every moment because you never know if you'll come back to these countries once you are finished here."
He would welcome a return to Europe at some stage: "I'd love to have another crack there ... but I am not thinking about that too much at the moment.
"If my club decides they don't want me then I will start looking at my options.
"I'd like to play in England, maybe a bit later in my career when I am a bit more mature body wise and football wise. You just never know what will happen in the future."
Sainsbury is satisfied with his contribution at a club backed by an electronics conglomerate which demanded an immediate return on its investment.
"There were a lot of expectations coming to a club which has spent a lot of money on foreign talent and I think I have handed myself very well," he said.
"We had a good season, finished second, above what many thought we'd be capable of, and still have the cup final to look forward to. If we win that then everyone willl be rapt.
"It's been a pleasure playing with quality players ... It takes you to a new level when you are alongside such big names as Alex, who is probably the best player I have played with.
"He just oozes class ... It's nice to have these guys on your side rather than against you."
Sainsbury believes his recent commanding form is indicative of the level his game has reached in China, despite the assertions of some that quitting the Dutch Eredivisie for an emerging competition was at best a sideways step.
"The biggest thing for me for me is to stay consistent ... No matter whether I am in China, Holland or Germany," he said.
"If I don't work extremely hard I will lose my Socceroos spot. It keeps me on my toes and I am trying to keep myself at international level.
"Certainly playing well for my club means also playing well for my country."
Though he scored in the 2-2 draw with the Saudis, Sainsbury, 24, knows where his real priorities lie.
"It's always nice to get on the scoresheet but I'd happily give that up for a couple of extra clean sheets," he said.
"Every game in the qualifiers is vital now and I don't care who scores, as long as we get the three points."
Sainsbury admits Australia have "lost a bit of momentum" after last month's draws with Saudi Arabia and Japan but sees no need for panic with the Socceroos still sitting second in Group B on the long and winding road to Russia 2018.
"Thailand will be tough for us to beat on home soil, but we're going there with same confidence we have against every opponent we face.
"If we take the three points to reach the halfway mark in qualifying and pick up the same amount of points in the next round of games then I think we'll end up topping the group."