GREATER Western Sydney's 75-point win over Hawthorn has been soured with news that star midfielder Ryan Griffen could miss 4-6 weeks with a back injury.

Griffen was a late withdrawal from the Hawks' clash and GWS coach Leon Cameron said post-match that the problem was worse than the club first thought. 

"'Griff' (Ryan Griffen) is going to be a little while unfortunately, his back is just playing up a little bit," he said.

"He's probably going to miss maybe 4-6 weeks so we're not going to risk a quality player like that."

As first reported by AFL.com.au, Griffen left the training track early on Wednesday in clear discomfort and clutching his lower back, and although GWS officials said he'd be right to go, the former Bulldog has failed to recover in time to face the Hawks. 

The 29-year-old suffered from lower back issues in his final season at the Bulldogs in 2014, before he sensationally walked out on the club and asked to be traded to the Giants. 

Griffen has averaged over 22 possessions – almost 11 of those contested – and six clearances per game so far this season, and the Giants will miss his experience around the footy against the reigning premiers.