The players' union has warned Parramatta against trying to bully players out of the club to squeeze under the salary cap amid hopes the latest scandal provides an opportunity to review the controversial third-party system.

The Eels are about $570,000 over the cap for this year and will need to shed players to ensure they play for competition points when they face South Sydney on May 13. The expected retirement of Anthony Watmough due to a career-ending knee injury may provide some relief, but others will need to be tapped on the shoulder for the Eels to keep alive their premiership campaign.

Rugby League Players' Association general president Clint Newton warned the embattled club not to pressure players out the door.

"No player should feel intimidated in a way that they feel like they have to move," Newton said.

"When you sign a contract – and we've gone through this process before – players shouldn't be punished for a club's mismanagement.

"I can't say that strongly enough. When these guys sign contracts, they expect them to be honoured, just like the club expects the player to honour their deals.

"The people in those positions, as club and game administrators, they need to act with the best integrity at heart and make sure they are following the rules."

Eels coach Brad Arthur refused to write off the season, believing the dramas would make the playing group even tighter.

"If we can find a way to be under the cap – we've got some work to do between now and next Friday – the equation is we need to win 12 from 15," Arthur said.

"We can do it. There is still hope. It's not like we've won two from nine, we're struggling and we can't play. It's still the same team, we don't need to change the way we play, we just need to be very good all the time.

"We can't afford to have off days, it can't happen. We can't shoot ourselves in the foot and beat ourselves like we did against Penrith."

The NRL and the RLPA will jointly review the TPA system, while their parties will also look at whether the salary cap, in its current form, is working.

"It potentially poses an opportunity for us around working out whether the system being used is the best system," Newton said.

We certainly look forward to being a part of this discussion.

"We're going to make sure that the players' well-being and rights are protected around this process.

"The fact of the matter is there's an allegation Parramatta has breached the rules and we have to offset that the best way possible. Working out whether this is the best system is a part of that."

The role of player managers will come under the microscope as the NRL continues its investigation. Asked whether players had a responsibility to ensure their payments were above board, Newton said: "Throughout this process the players are there to play football and the administrators are there to administer the club."