ALIIR Aliir is ready to embrace his mantle as Sydney's No.1 ruckman. 

Admittedly, it's not like the athletic key defender had any choice.

When Callum Sinclair dislocated his shoulder in the opening seconds of the Swans' win over Gold Coast last week, Aliir was the man coach John Longmire turned to for a temporary fix.

But when Sinclair popped his shoulder again on quarter-time after bravely attempting to play on, the Swans knew Aliir would have to carry the ruck duties for the near future.

It might be his job for the rest of 2019 if Sinclair’s serious injury doesn't respond to rehabilitation and requires surgery.

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Injuries to Sam Naismith (knee) and Darcy Cameron (quad) on top of the loss of Sinclair meant Longmire's usually plentiful big-man stocks had been whittled down to one, and mid-season recruit and basketball convert Michael Knoll isn't ready for senior duty.

Aliir will lead Sydney’s ruck division at the MCG this Saturday against Essendon – a club that lost its own premier big man Tom Bellchambers to a calf injury – but the 24-year-old Swan’s attitude isn’t unexpected.

"It's good that 'Horse' (Longmire) trusts that I can do the job for the team, and if that’s what it takes then I'll do it," Aliir said.

"He just told me to go out and play footy.

"Injuries happen in footy so you just have to adapt and move forward.

"It might only be for a couple of weeks, so I'm just going to try and do it to the best of my ability and help the team win."

Sydney has the luxury of having one of the modern game's greatest big men on its coaching staff.

Former West Coast premiership star and six-time All Australian Dean Cox has spent the week schooling Aliir on the tools of the trade he dominated in a 290-game career.

Aliir, who will take on former Fremantle ruckman Zac Clarke on Saturday, said Cox hasn't been too technical in the lead-up to the Bombers clash.

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Like he did against the Suns' Jarrod Witts last week, Aliir plans to put his mobility to good use on the MCG deck.

"To have a guy like 'Coxy' to learn from (is amazing), and he keeps it simple too because he knows I'm not a ruckman," he said.

"My strength is jumping, not necessarily wrestling, but if I have to do it I can.

"I just have to keep them guessing.

"I'm not the usual type of ruckman so I'll be moving around and trying to get the ball in my hands, then pushing forward and trying to hurt them the other way."

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