Parramatta has lodged a complaint with the NRL, claiming the NZ Warriors tried to poach rookie five-eighth Dylan Brown.
Under league rules, no club is allowed to speak with the 18-year-old, who is under contract with the Eels until the end of 2020, until November, The Daily Telegraph reports.
Parramatta claims Warriors recruitment boss Peter O'Sullivan's meeting with Brown and manager Gavin Orr breached those rules.
O'Sullivan admits to the meeting, but says he cut off talks when Orr realised he had made a mistake about his client's contract.
"We approached [Brown] on the understanding he was off contract at the end of 2019, which we're entitled to do," said Warriors chief executive Cameron George.
"It was later cleared up that he had a variation [in his Parramatta contract] that committed him until 2020 and that was it."
The Sydney Morning Herald reports the Warriors tabled an offer worth AU$3 million, which would have been the biggest contract ever for a player yet to make a first-grade appearance.
The Herald claims to have a copy of the contract, which would have secured his services until the end of 2025 - six seasons.
Brown's name was floated in November, as a possible replacement for Warriors star Shaun Johnson, who left the club to join Cronulla.
He is understood to be on a two-year development contract with Parramatta, worth $60,000 per season, but the Eels are keen to extend that deal. Brown, 18, is expected to partner Mitchell Moses in the halves, after Corey Norman left to join St George Dragons.
League rules prohibit teams from approaching players from other teams until November 1 in the year before their contract expires.
If the NRL decides the Warriors have a case to answer, they - and particularly O'Sullivan - could face sanctions.
O'Sullivan has a reputation for 'discovering' league stars like Greg Inglis, Israel Folau and Roger Tuivasa-Sheck, but was deregistered in 2016, after breaching NRL betting rules and having financial dealings with notorious punter Eddie Hayson.
He was allowed to join the Warriors last year, after his deregistration ended.