Following a Fairfax report which claims a cashed-up CSL club is preparing to head-hunt the Socceroos coach, the agent warned that Postecoglou's hands "would be tied" over signings, with club presidents, sporting directors and agents dictating player recruitment.
He added that with the CSL transfer window now closed he would be saddled with a squad not of his choosing, "even if he did have a small say" on who to bring in.
"It would be foolhardy for Mr Postecoglou to consider any offers here right now," said the agent, who has been involved in several deals involving Australian players over the years.
"I am sure he is too smart to do something so stupid.
"He would have no say in signings - and the window has now just about closed anyway.
"The top five clubs (Shanghai SIPG, Jiangsu Sainty, Guangzhou Evergrande, Shanghai Shenhua and Beijing Guoan) all have coaches for the season (which kicks off on Match 23), which means he'd probably end up at a less well known team.
"Only a tiny handful of foreign managers have survived in the CSL (since its inception in 1993) for more than one or two years and players don't have too much security either.
"It's a pretty ruthless environment."
Postecoglou, who has 18 months to run on his contract with the FFA, is at the mid-point of an exacting qualification campaign for Russia 2018, with the Confederations Cup looming in June.
And it's highly speculative to imagine him exiting the Socceroos set up prematurely, unless of course they were to fail to qualify for the World Cup.
He will also be aware of the pitfalls of Asia, with former Socceroos assistant Graham Arnold surviving just eight games during his ill-fated tenure with J-League club Vegalta Sendai in 2014.
"You have to know the marketplace, the mentality of the people and a bit about the culture," added the agent.
"It's not easy for any coach coming here, especially as so much is expected of them.
"When it comes to signings, club presidents and sporting directors force players on you and you have to live with it."
The agent cited the example of Western Sydney Wanderers coach Tony Popovic, who rejected an offer to take charge at Shanghai Shenhua last November after concluding that there would to too much interference from above in player recruitment.
"I can totally understand why he said no to the offer," he added. "After the way they were beaten by Brisbane in the ACL, you can see it was the right decision.
"Many people were surprised that he didn't take the job but he must have known the job he was being given was impossible."