The big tackling forward is understood to have been offered a four-year deal to join the Pies in a defining season for coach Nathan Buckley.

It had been widely expected over recent months that Mayne would leave Fremantle and was headed to North Melbourne in a savage player list shake-up at the Kangaroos.

He is understood to have met with Pies officials early this week when a more attractive deal to join Collingwood was tabled which trumped an appealing three-year contract from North.

The embattled Roos are also bracing for the potential loss of star on-baller Daniel Wells.

An announcement on where Wells will play next season is tipped for as soon as North finish their finals campaign this month which could be as early as next week if they are bundled out by a more fancied Adelaide in Adelaide on Saturday night.

The Pies are believed to be hot in the running to secure the out-of-contract 242-game veteran with an extra season in a package offer to the 2002 national draft number two pick.

Wells, 31, wants another two seasons in a new deal, with only one on offer from Roos management in the wake of controversial decisions not to extend careers of North big names Brent Harvey, Drew Petrie, Michael Firrito and Nick Dal Santo.

A Pies offer to Wells is believed to be for two seasons.

Mayne turns 27 in November and has weighed up deals to continue his career in Victoria as an unrestricted free agent after nine Dockers seasons and 172 senior games where he has booted 196 goals and can also play as a key defender.

The value of Mayne's contract is critical in possible compensation to Fremantle as their list managers clamber to rebuild playing stocks through trading and this year's draft after a highly anticipated big departure of existing Dockers.

A handsome contract for Mayne is likely to be compensated with at least a second-round draft pick.

Dockers management is expected to land triple Hawthorn premiership winger Brad Hill, disgruntled Greater Western Sydney forward Cam McCarthy and borderline Geelong big man Shane Kersten who is out of contract and unable to secure a regular berth in the strong Cats unit.

They will all command hefty trade deals with a swap of players or more likely draft picks for this November or next year's selections.

Dockers recruiters are also still heavily into bidding in a fierce tug-of-war with arch enemy West Coast for athletic Giants big man Rory Lobb, who is not out of contract until the end of next season.

The classy on-baller would command a swap of early round draft picks if Giants officials even seriously contemplate releasing one of the most improved players in the business with another season to run on his contract.

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