Manly chief executive Lyall Gorman is not confident the injury-hit Sea Eagles can compile a list of 30 players by June 30, which is the NRL's deadline for all 16 clubs, after releasing Jackson Hastings on Tuesday.
"I'm not convinced we can," Gorman told NRL.com. "But I'm pretty sure if we went to the NRL on the basis of where we sit, you'd hope to think there'd be an understanding of the current situation.
"It's an extraordinary set of circumstances."
The 14th-placed Sea Eagles confirmed this week another two players - hooker Api Koroisau (foot) and winger Akuila Uate (ankle) - would not be able to return to the field this year. They join five-eighth Lachlan Croker and Curtis Sironen (both knee reconstructions) as season-ending injuries.
Forwards Jack Gosiewski (arm) and Lewis Brown (shoulder) are another month away from returning.
Hastings - who has been released from the remaining four months of his contract and is likely to continue his career in the Super League - was one of the three recognised No.9s in the Sea Eagles squad along with Korisau and Brown.
Hastings took to Instagram on Tuesday with the message: "Never regret anything that has happened in your life. It cannot be changed, undone or forgotten. So take it as a lesson and move on."
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With the trio unavailable, Manly named former under 20s premiership-winning captain Manase Fainu to play Penrith in the Telstra Premiership's round-16 clash at Panthers Stadium on Saturday.
Manly submitted Fainu's name for the round-15 match against the Dragons but it was rejected by the NRL because Hastings was still on the books.
"We hope to get an exemption for him as a development player. We'll see where that lands," Gorman said.
"Obviously Api is gone for the season. And now Lewie (Brown) is also gone and Jackson has left. So we hope we can get a favourable response from the NRL.
"The bottom line is we don't have hookers left. We've made application on that basis."
The club has until 3pm Thursday to submit its appeal but it is believed the NRL will not reject Fainu this time around.
Gorman has spent the past two days at NRL headquarters pleading Manly's case before Ian Callinan, QC, who heads the appeals committee, after Manly were slugged a $750,000 fine and had $660,000 of their salary cap cut over two seasons due to breaches in player payments.
"I haven't seen Jackson personally as I've had two very busy days but I will be sending him a message," Gorman said.
"It was a mutual decision between his management and our club and we wish him well for the next stage of his career."
The 22-year-old played 13 games for Manly in two seasons and 34 for the Roosters, where he made his NRL debut in 2014.
Manly second-rower Shaun Lane will depart the club at season's end with Parramatta viewed as his likely destination for the next three years.
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"With the way our salary cap is at the moment we couldn't match an offer that was put to him," Gorman said.
"We brought him across from the Warriors and he's developed so well under the coaching of Trent (Barrett) and from being within our playing group.
"So it is disappointing to see him go. But it's the world we live in with player movements. We've got to come to grips with that and move forward."