So far, Steven Davis, Allan McGregor, Kyle Lafferty, Jamie Ness, Steven Naismith, Steven Whittaker, Sone Aluko and Rhys McCabe have confirmed objections to transferring their contracts to Green's Sevco company. The former Sheffield United chief executive's consortium completed the purchase of the business and assets of Rangers for £5.5 million when the club was consigned to liquidation.
The squad are due to report back to Murray Park for the start of pre-season training on Thursday, but only Lee McCulloch, Lee Wallace and Kyle Hutton have indicated they plan to commit to the new regime, although Dorin Goian could follow suit.
When quizzed about the eight who have refused to transfer their contracts under TUPE employment regulations, Green told Sky Sports News: "I'm very, very disappointed of course. Particularly so late in the proceedings.
"It is clear in the regulations, if someone has an objection they have to notify within 24 hours, this is nearly two weeks. I think this is just opportunism. We will definitely challenge it, yes."
Colin Leckey, partner in the sports and employment groups at law firm Lewis Silkin, believes Green might have a case for blocking their exit, although there are several complicating factors.
Leckey said: "On the face of it, the law is straightforward, and supportive of the players' position: under the TUPE regulations, if an employee objects, their contract does not transfer, and nor do any rights, powers, duties or liabilities connected with it.
"They have no right to any severance pay, but they do become free agents - clearly, this is the players' aim here. However, reports raise an intriguing question as to whether at least some of the players have left it too late."
Asked whether he expects more players to try to quit the Ibrox side, Green added: "I've learnt not to expect the expected at Rangers."
Rangers legend Sandy Jardine has accused the eight players who are aiming to leave Ibrox for free of greed after they refused to transfer their contracts to Charles Green's newco.
Jardine - who spent 17 years as a player at Rangers and still works behind the scenes at the club - told RangersTV: "I am dismayed and disappointed by the actions of the eight players."
Some of the players have cited uncertainty over which division Rangers will play in next season and lack of information about Green and his investors as reasons for their decision.
However, Jardine is angry that players are opting to walk away for free after negotiating clauses into their contracts in March that would allow them to leave for reduced transfer fees in return for accepting wage cuts of up to 75 per cent until the end of the season.
Jardine added: "You have to say that if the players were up front and honest you would respect them more. What they have done is seen an opportunity - whether it is them or their agents - to maximise their income.
"The players took a salary sacrifice but for that they got clauses in their contracts which would allow them to leave on rock bottom prices if clubs came in for them. I have to be honest and I think the players have used our predicament to their gain.
"Ally McCoist gave a statement last week where he asked the players not to kid anyone on and to be up front and honest with the supporters."