Football Federation Australia chief executive David Gallop said he is not "100 per cent confident" the A-League season will start as scheduled.
An ongoing dispute between FFA and Professional Footballers Australia (PFA) regarding the collective bargaining agreement has continued to spill over, with the PFA demanding on Tuesday of up to $3million Australian dollars' worth of increases to the salary cap over the next two years.
The A-League clubs collectively rejected PFA's demands in a statement on Wednesday, and Gallop said the PFA's sudden rise in demands - including a continued push for more investment into the Australian national women's team, the Matildas - was not helping their cause.
"We've invested a lot in their program in the last year to prepare [the Matildas] for Canada and the World Cup," Gallop told reporters in Melbourne.
"Now we've provided an opportunity for them to play the world champions, 60,000 tickets have been sold.
"Yes we would love to pay them more but unannounced, fresh demands [made by the PFA] yesterday is no way to go about it."
As a result, Gallop added that the A-League season - set to start when the Western Sydney Wanderers host Brisbane Roar on October 8 - could be pushed back as a result of the impasse.
Meanwhile, Adelaide United chairman Greg Griffin led the clubs' slamming of the PFA's demands to raise the salary cap by $1m in 2015-16, and another $2m in 16-17.
"The PFA has shown its reckless regard for the clubs who collectively employ over 200 professional players," Griffin said.
"The demand for another $3 million in payments is a dangerous folly, especially in such a young league. Do they want to send clubs broke before they comprehend the damage?
"We keep hearing from the PFA about respect for players. What about respect for clubs, their staff, members and sponsors? Respect is a two way street."
