Whether it actually represents a big offer is highly subjective. By the end of it, he would be on $650,000 a year which would not be considered a great deal for a star halfback.
And there are also potential pitfalls in offering a young player such a long deal as the Bulldogs found out with Sonny Bill Williams years ago.
Officially, Brown can only be approached in November but in an apparent mix-up, O'Sullivan made a contract offer to to Brown's manager Gavin Orr believing there was only one year left on his Parramatta contract. The Eels have reportedly complained to the NRL.
"We approached [Brown] on the understanding he was off contract at the end of 2019, which we're entitled to do," Warriors CEO Cameron George said.
"It was later cleared up [by his agent] that he had a variation [in his Parramatta contract] that committed him until 2020 and that was it."
The offer involves paying Brown $300,000 next year, $350,000 for 2021, $450,000 in 2022, $500,000 in 2023, $550,000 in 2024 and $650,000 in 2025. There is also a $60,000 relocation payment.
It involves a significant "front loading" so Brown can buy a house in Auckland.
Brown appeared for Parramatta's feeder club Wentworthville last year, who were coached by new Warriors assistant Nathan Cayless.
The SMH reported that "Parramatta officials are aware of the Warriors offer and are furious about the attempt to sign their most promising star.
O'Sullivan was deregistered by the NRL in 2016 while working for the Sydney Roosters over his link to Australian punter Eddie Hayson, who had deposited money in O'Sullivan's TAB account. He was also the Melbourne Storm's recruitment boss during th club's salary cap scandal, although he was never charged by the NRL.
O'Sullivan has a brilliant CV as a scout, having uncovered Billy Slater, Greg Inglis and Israel Folau. He was also the man who signed Roger Tuivasa-Sheck to the Roosters in 2011, even though the Auckland-based schoolboy star was on the Blues and Warriors radars.