The Parramatta Eels have been found $3 million in breach of the salary cap since 2013, with NRL chief executive Todd Greenberg describing the 12 point docking as a "heartbreaking day" for the club's fans and players.

Greenberg and the NRL's head of integrity unit fronted the media on Tuesday morning, shedding light on the three month investigation which has seen the club's finals hopes dashed as well as a $1 million fine and the deregistration of five officials.

"This is the day no one in rugby league wanted to see," Greenberg said.

"It's a tough day for one our great clubs, a tough day for the game and a truly heartbreaking day for Parramatta fans and their players. Sometimes the hardest thing to do is also the right thing to do. Regrettably the results are not only disappointing, they are a stain on our game."

Nick Weeks unveiled the depth of deception by the club, with the evidence compiled suggesting the Eels had $3 million of undisclosed payments to players since 2013 to answer for.

"In monetary terms, we estimate the club made promises of remuneration that haven't been disclosed to the NRL at about $3 million since 2013 in aggregate," Weeks said.

However, coach Brad Arthur told media the players had not given up making the finals come September, a mathematical possibility should the club get itself under the salary cap before their next game against the Rabbitohs at Pirtek Stadium on May 13.

"(The players) are defiant," Arthur said. "Twelve (wins) from 15 (games) - that's the situation and they're determined. We're very disappointed, but there's still hope for us."

"At the start of the year we wanted to play finals football and nothing's changed and we're really commited to tyhring to do our best to make sure that can still happen come 26 years rounds.

"We've won 68 per cent of our games at the moment, we've got to win 80 per cent of our games.

"It's tough but we're prepared for the fight and we're really committed to trying to do our best to make sure that can still happen come after 26 rounds.

"We've won 68 per cent of our games at the moment. We've got to win 80 per cent of our games.

"It's tough but we're prepared for the fight."

While the NRL came down hard on the Melbourne Storm and stripped the club of two premierships and a right to compete for points in 2010, Greenberg didn't want to see a repeat at Parramatta.

The NRL boss said he would happy if Parramatta makes a miraculous run to the finals and began accumulating points when they become salary cap compliant, which won't occur until they shed $570,000 worth of talent.

"I didn't make the decision on Melbourne Storm but I'm making the decision today," Greenberg said.

"The decision we've made gives you an eye to the future, it gives some hope to the club and I hope they take that. I watched Melbourne Storm fans and players have to continue to play a season without the ability to accrue points, I thought that was soul destroying both for the players and fans.

"I've tried very hard to find a way forward here that Parramatta Eels can take a step forward here. If Paramatta win every game under the salary cap, I will be very happy. But they have to comply with the salary cap like every one of the other 15 clubs."

Greenberg and Weeks held a meeting with Eels players and coaching staff in Parramatta on Tuesday morning.

The NRL chief executive said he felt sorry for the playing group, but insists it was important they heard the message from the governing body despite the clear disappointment about the verdict.

"I think it would be fair to say they were shattered. I really felt for players this morning and I was desperate to make sure Nick and I faced them face to face this morning and they found out this news from us directly," Greenberg said.

"I feel really sorry for the players. This is a difficult time and they've worked really hard and played some great footy but I have a duty and the game has a duty to represent 16 clubs and 16 groups of fans and that's what I've done today.

"I wouldn't call it pushback [from the players], I thought they were very respectful. I think Brad Arthur has done a wonderful job with that group of men and he will need to do a really good job in the coming weeks and months to keep them all together and I'm sure he can do that."

The Eels released a statement on Sunday night threatening legal action, with their handling of the entire investigation disappointing the NRL.

"I think the Parramatta Eels over the last couple of months have continued to do what they have done, which is continue to deny there are issues at their club," Greenberg said.