COLEMAN Medal leader Jeremy Cameron is out of Saturday's Sydney Derby at Giants Stadium, with exciting defender Connor Idun named to debut as his replacement.

Cameron was picked in Greater Western Sydney's team to take on the Swans on Thursday night but has withdrawn with calf tightness.

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GWS officials will be sweating on Cameron's fitness with just four games remaining in the home and away season, with even a slight strain likely to rule him out for at least a couple of games.

The 26-year-old has kicked 57 goals from 18 games this season and leads North Melbourne's Ben Brown by nine majors in the Coleman race.

While the loss of their star goalkicker is a blow for the Giants, the inclusion of Idun, who was born in London to an Australian mother and African father, is a good story for the Giants.

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The club traded future picks to get back into last year's NAB AFL Draft to select him at pick No.61.

He's played 15 NEAFL games this season as a defender, where his athleticism and speed has been impressive and allowed him to play tall or small, and anywhere in the back 50.

It's been a big week for the Geelong Falcons product, who turned 19 on Monday.

Teammates surprised him with a birthday cake at dinner to celebrate the milestone and he was even more shocked by GWS coach Leon Cameron on Friday morning.

"I just came to training expecting to have a captain's run with the NEAFL, but one of the managers told me we had a team meeting," he said.

"Leon started talking about a debutant and my ears pricked up, and thankfully it was my name he mentioned.

"The boys got around me and the rest is a blur.

"Mum didn't really believe me when I told her, she was pretty shocked.

"It's a bit surreal, this time last year I didn't think I was even going to get drafted, so to be making my debut in a derby, I'm pinching myself."

Idun has thrived in his one on one contests in the reserves and expects to fill the same role against the Swans.

Fellow draftee Nick Blakey or Daniel Menzel loom as potential opponents.

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He said having the experience of Heath Shaw and co-captain Phil Davis in the backline will help ease his first-game jitters, especially in the intense environment of a derby.

"I'm going to be pretty nervous, but 'Heater' is very good at communicating and Phil is a very calm head to have on the field, so it'll be good to have them around me," he said.

"They just want me to have fun and bring the energy to my role as a lockdown defender.

"I'm ready for the battle, but I'm a pretty relaxed character and I'll have five other backline brothers out there to back me up, so I'm not too worried about that."

Meanwhile, Carlton will be without key defender Liam Jones at Marvel Stadium against West Coast on Sunday following the passing of his mother.

Ex-Saints tall Hugh Goddard has been called up to cover for Jones ahead of a looming battle with one of West Coast's twin towers Josh Kennedy and Jack Darling, who combined for nine goals against North Melbourne last round.

Hugh Goddard will make his second appearance of the season.

Youngster Paddy Dow has been left out after coming in as a late inclusion against Adelaide and gathering just four touches, with Zac Fisher back from illness.

The Eagles have confirmed the solitary change with skipper Shannon Hurn coming back from a calf strain for emerging defender Francis Watson.

Injury-hit Collingwood has axed Ben Crocker amid three changes ahead of a danger game with Gold Coast at the MCG.

The Magpies have lost star Jordan De Goey (hamstring) and youngster Isaac Quaynor (foot) to injury, but regained Taylor Adams and Levi Greenwood, while Rupert Wills has been called up.

Taylor Adams is a confirmed starter for the Pies.

The Suns have brought back dynamic trio Jack Martin, Ben Ainsworth and Jack Bowes as they seek to end a 14-game losing streak, while Charlie Ballard also returns. 

In the final game of round 20, Brisbane will take a settled line-up into its home game against the Western Bulldogs, only bringing back star defender Harris Andrews from suspension for veteran Josh Walker. 

The Dogs recalled ex-Lions tall Josh Schache, Matt Suckling and Toby McLean after last round's hammering of Fremantle lifted his side from 12th to ninth.

Friday, August 2

North Melbourne v Hawthorn at Marvel Stadium, 7.50pm AEST

NORTH MELBOURNE

In: S.Thompson, K.Turner
Out: S.Atley (knee), J.Anderson

HAWTHORN

In: T.O'Brien
Out: J.Ceglar

Saturday, August 3

Essendon v Port Adelaide at Marvel Stadium, 1.45pm AEST

ESSENDON

In: O.Fantasia, C.McKenna
Out: B.McNiece, J.Laverde

PORT ADELAIDE

In: C.Dixon, P.Ladhams, T.Marshall
Out: D.Howard, S.Lycett, J.Garner 

Greater Western Sydney v Sydney at Giants Stadium, 2.10pm AEST

GREATER WESTERN SYDNEY

In: B.Deledio, J.Stein, C.Idun
Out: S.Taylor (hamstring), D.Lloyd (calf), J.Cameron (calf)
New: Connor Idun (Geelong U18)

SYDNEY

In: O.Florent, J.Rose, D.Menzel, K.Jack
Out: L.Melican, R.Stoddart, D.Rampe (eye), C.O'Riordan (groin)

Fremantle v Geelong at Optus Stadium, 2.35pm AWST

FREMANTLE

In: E.Hughes, B.Banfield, M.Crowden, J.Carter, S.Switkowski
Out: H.Ballantyne, B.Bewley, N.Wilson (toe), L.Ryan (hamstring), R.Lobb (shoulder)
New: Jason Carter (Claremont)

GEELONG

In: Z.Tuohy, G.Rohan
Out: H.Taylor (managed), J.Parsons

Melbourne v Richmond at the MCG, 7.25pm AEST

MELBOURNE

In: K.Dunkley, J.Melksham, B.Preuss, J.Kennedy Harris
Out: J.Wagner, A.Neal-Bullen, N.Jetta (knee), T.Smith (foot) 

RICHMOND

In: J.Caddy, D.Butler
Out: S.Stack (calf), T.Cotchin (hamstring)

Adelaide v St Kilda at Adelaide Oval, 7.10pm ACST

ADELAIDE

In: R.Douglas, E.Betts, B.Gibbs, D.Fogarty
Out: P.Seedsman, P.Wilson, J.Jenkins, T.Stengle

ST KILDA

In: J.Battle, D.McKenzie, M.Parker
Out: B.Acres (shoulder), J.Newnes (illness), B.Paton (illness)

Sunday, August 4

Collingwood v Gold Coast at the MCG, 1.10pm AEST

COLLINGWOOD

In: T.Adams, L.Greenwood, R.Wills
Out: I.Quaynor (foot), J.De Goey (hamstring), B.Crocker

GOLD COAST

In: C.Ballard, J.Martin, B.Ainsworth, J.Bowes
Out: J.Joyce, J.Hombsch (ankle), C.Ellis, J.Heron

Carlton v West Coast at Marvel Stadium, 3.20pm AEST

CARLTON

In: Z.Fisher, H.Goddard
Out: P.Dow, L.Jones (personal)

WEST COAST

In: S.Hurn 
Out: F.Watson

Brisbane v Western Bulldogs at the Gabba, 4.40pm AEST

BRISBANE

In: H.Andrews
Out: J.Walker

WESTERN BULLDOGS

In: M.Suckling, J.Schache, T.McLean
Out: D.Morris (knee), T.Duryea (groin soreness), R.West