Ellison, whose finest hour was when he scored a hat-trick in Wigan's Premiership final victory over St Helens in 1996, was seen as surplus to requirements with the signing of the Australian Mark Bell, and the scheduled arrival of his fellow countryman, Wendell Sailor, next year.
Castleford were also hoping to confirm the signing on a free transfer of Wigan's French second row Gael Tallec today. Their enquiry for Steve Holgate and Bradford's for Darryl Cardiss came to nothing. Castleford see Ellison as a replacement for Chris Smith, who they have sold to St Helens.
Meanwhile, Wigan have rejected any suggestion that they will let Jason Robinson on Gary Connolly to go Australia in exchange for Sailor, whose services the Brisbane Broncos say they will not give up without a fight.
"We're not expecting to have him here this season," the Wigan chairman, Mike Nolan, said. "It sounds ridiculous, but we don't really need him this year. We have budgeted for him next year and it could be the courts that decide whether the option Brisbane claim to have on him is valid."
Wigan's chief executive, Phil Clark, who is in Australia, is meeting the ARL to clarify the position of Connolly who signed a contract to join the organisation in 1999, before the reunification of the game Down Under.
Wigan's winter signing from the London Broncos, Tony Mestrov, will miss the start of the Super League season. The Australian prop suffered a compound fracture of a finger in the friendly at Leigh on Sunday.
The signings of two world- class players will be unveiled today, with the New Zealand stand-off Dave Watson joining Sheffield Eagles and the Australian Test prop Mark Carroll linking up with London. Watson, who has played for Whitehaven, Hull KR, Halifax and Bradford, has been with Cronulla and Gold Coast since being suspended in Britain for failing to take a drugs test, having failed one for cannabis in the past.
London have cleared the decks today for the official announcement of what their chairman, Richard Branson, calls "the biggest name to join English rugby league for 10 years".
- Dave HadfieldReuse content