Sage issued an open letter to Glory members on Sunday criticising Professional Footballers Australia (PFA) for rejecting a 30% pay cut for the 2020-21 campaign.
A-League clubs and the players' union have been in talks to broker a new collective bargaining agreement for a competition that has been hit hard by the COVID-19 pandemic.
With uncertainty over gate figures and the future of a broadcast deal, Sage said the reality was players had to accept revenues were down across the competition and clubs needed to cut costs.
"The clubs are the only group prepared to put money into the game at the moment," Sage's statement said.
"In Perth Glory's case, our revenue from the broadcast rights has dropped by almost 50% and in light of the unprecedented worldwide pandemic, our gate receipts remain uncertain because of WA's hard borders.
"These border restrictions will be another huge hit to our revenue of about 30%.
"So in total, Glory's total revenue may drop by up to 75% for the upcoming season."
Sage said with the PFA and Australian Professional Football Clubs' Association (APFCA) failing to reach a new agreement, he is set to stand down players and staff.
A short-term deal -- which involved heavy player pay cuts -- was then agreed on in order to complete the campaign.
"Some other clubs will also stand down players and staff, other clubs may pay 50% of current salaries, but all owners are unanimous in offering the players a 30% reduction for the upcoming season because that's all the money there is," Sage said.
The PFA were quick to respond to Sage's claims, saying talks were ongoing with clubs and Glory players were set to meet with their club on Monday.
"Attempts to pressure the players through threats and misleading commentary is unhelpful and damaging, particularly while the players continue to work in good faith to reach a solution," co-chief executive Beau Busch said.
The PFA has previously stated players have already had to make a financial sacrifice and it's unfair for them to be asked to accept further cuts for next season.
The FFA is not directly involved in the negotiations but chief executive James Johnson has warned the governing body will intervene if the two parties cannot reach an agreement.