GREATER Western Sydney will be hoping a massive injury toll of key defenders doesn't result in Richmond spearhead Jack Riewoldt producing a bumper haul like his 11-goal bag against the Giants last season.

The Giants have an acute shortage of key defenders left to tackle Richmond's formidable array of tall forward timber in Saturday's clash at the MCG.

The Giants will be without their four main key backs with Nick Haynes (groin) joining long-term casualties Phil Davis (ankle), Tim Mohr (knee) and Joel Patfull (ribs), while Lachie Plowman has had just one game back in the reserves after dislocating an elbow in January.

Aidan Corr (22 senior games) and rookie Caleb Marchbank (one) are the only fit specialist key defenders, as the Giants strive to quell the Tiger trio of Riewoldt, Ty Vickery and Ben Griffiths.

Davis, Mohr and Haynes all missed the game at Spotless Stadium last year, when Riewoldt booted his career-best bag and Corr primarily had the job on the Tiger spearhead.

Co-captain Callan Ward was adamant GWS still had enough defensive depth to compete against Richmond's talls.

"We've got plenty of guys who can come in and cover those sort of guys in the back six," Ward said.

He wasn't listening to the naysayers who have tipped the Giants to plummet out of the top eight after suffering successive losses for the first time this season.

"Internally we're still really confident," Ward said.

"We still think we're playing some really good footy and we still believe we can beat any team out there."

The Giants also remain short in the ruck department, with Shane Mumford out for the season and his most experienced backup Andrew Phillips unlikely after not playing for the past three weeks.

Tom Scully is available again after illness forced him to withdraw from the Giants' last game against North Melbourne before last week's bye.

Richmond has won five of its past six, notching away victories over Fremantle and the Sydney Swans in that time, but Giants coach Leon Cameron wasn't fazed at playing the Tigers in the midst of a purple patch.

"The first 10 or 15 minutes for us is so important because you want to get over that bye week, get over that rustiness, get your second wind," Cameron said.

"Richmond have already played two games after their bye so they are rolling now, and we must make sure that we get rolling early."