Greater Western Sydney star Lachie Whitfield is tipped to miss the Giants' Round 1 clash against St Kilda, with a a return date unclear for the flashy midfielder.

Whitfield has battled a bruised liver during the pre-season and has only just started running after copping a nasty hit at training last month, with the The 26-year-old revealing his health struggles to AFL.com.au's Michael Whiting.

"You do a whole pre-season ready to go for round one and I won't be playing round one now," he said.

"I can't do much exercise at all because the liver is inflamed, swollen up, which has then pushed up my right lung from where it should be.

"Breathing is pretty hard to do, especially through exercise. I've tried a fair bit of running and I'm not fully agreeing with that at the minute.

"I just need the liver to shrink in size, so the lung can cope with it all."

Whitfield revealed his surprise when he received scans on what was assumed to be a rib injury.

"I got the scan and was told there was a little bleed in there," he said.

"Sometimes if the bleed is miniature you can avoid hospital, but the pain continued and … I ended up spending nine nights in hospital.

"It was a bit worse than we first thought."

Whitfield became the first ever Giant to win a second Best and Fairest at the club in 2020, joining defender Nick Haynes on the podium in front of his peers.

The news follows setbacks for fellow recruit Braydon Preuss and defender Adam Kennedy, who have both undergone shoulder surgery and will miss a majority of the season.

Teammates Jesse Hogan (quad), Phil Davis (knee) and Bobby Hill (concussion) are also under an injury cloud.

The Giants will host the Saints at GIANTS Stadium on Sunday, March 21.