IMPRESSIVE young midfielder Lachie Whitfield's season is over after he underwent shoulder surgery on Tuesday.

The No.1 pick in the 2012 NAB AFL Draft, Whitfield has undergone a shoulder reconstruction and won't play for Greater Western Sydney again this year.

Whitfield, who turns 20 on Friday, also requires surgery on his foot, which will be carried out before the end of the season.

Following 19 appearances in a strong rookie year, Whitfield played a further 11 games this season, averaging 20 possessions, almost six marks and two tackles per game.

He was absent between rounds 3-7 this year with a foot injury.

“Unfortunately Lachie has had an injury interrupted season and it’s in his best interests to have this surgery now so he can be ready to start pre-season training," GWS football manager Graeme Allan said.

“We look forward to Lachie making a full recovery and being available for the start of the 2015 season.”

An excellent ball user, the highlights of Whitfield's second season included 32 possessions and nine marks in a loss to Hawthorn and another 32 disposals in the victory over the Brisbane Lions in round 13.

He kicked three goals and had 20 touches against Fremantle on Sunday.

In other injury news from the Giants, Adam Treloar and forward Jon Patton will undergo fitness tests later this week after they missed the match against the Dockers with groin injuries.

GWS hosts Geelong at Spotless Stadium on Saturday night.

Stephen Coniglio (thumb) will be absent for another five weeks following surgery, while defenders Stephen Gilham (hand) and Curtly Hampton (shoulder) should return in the coming weeks.

Vice-captain Heath Shaw (concussion) faces further assessment after the Giants' bye after it was discovered he had bleeding on the brain from the heavy hit he suffered back in round 15.