Tuesday's AFL pre-season draft is expected to be a ruckman's merry-go-round, with as many as five of the league's big men tipped to be given new homes.

That would make up more than half of the draft's nine possible selections.

The pre-season draft is open only to the eight clubs which have left at least one space on their playing lists, with Carlton having room to choose two players.

The Blues, which have the first pick, have committed to drafting ex-St Kilda ruckman Cain Ackland to fill the vacancy left by the retirement of Barnaby French.

The Saints, in turn, are expected to fill the gap left by Ackland's departure by drafting ex-Adelaide big man Matthew Clarke.

The Crows will be left vulnerable in the ruck after losing Clarke and Rhett Biglands, who is expected to miss the 2007 season with a knee injury, but they do not have a pick on Tuesday.

The Saints had already strengthened their ruck division by trading with West Coast for Michael Gardiner, before Ackland's decision to join the Blues prompted them to also pursue Clarke.

Carlton is expected to be involved in a separate shuffling of ruckmen between clubs, with Collingwood believed to be committed to picking up ex-Blues 24-year-old Chris Bryan.

To fill that gap, the Blues are likely to pick up discarded Magpies 22-year-old Cameron Cloke with their second selection, the final pick of the draft.

Hawthorn is also likely to bolster its ruck depth by recruiting former Essendon fringe player Tristan Cartledge, after losing Peter Everitt to Sydney via the trade market.

Essendon, which has the second selection, has committed to former Brisbane premiership fullback Mal Michael in a recruiting coup.

Michael's decision to reverse retirement plans angered the Lions, who released him from his playing contract, but the move was cleared by the AFL after an investigation.

Richmond is expected to give Geelong's four-time leading goalkicker Kent Kingsley a second chance at an AFL career, with the 28-year-old having trained at Punt Road after being axed by the Cats.

The rookie draft - for players aged under 23, or who are over 23 but have not been previously registered for a draft - will be held immediately after the pre-season draft, with clubs having a total of 64 selections.

Players on a club's rookie list can be upgraded onto the primary list to temporarily replace a player who has a long-term injury, or to permanently fill vacancies made by post-season delistings.

Stars whose career started via the rookie draft include Dean Cox, Brett Kirk, Ben Rutten, Mal Michael, Aaron Davey, Russell Robertson and this year's Rising Star winner Danyle Pearce.