Greater Western Sydney's thrilling win over the Western Bulldogs has come at a cost, with defender Nick Haynes set to miss around 10 weeks with a hamstring injury.

Haynes sustained the injury after landing awkwardly in a marking contest late in the game on Friday night.

The 24-year-old will not require surgery, however, will undergo an extensive rehabilitation program.

"We're all really disappointed for Nick, who's been in terrific form early in the season," GWS performance manager David Joyce told the club's website.

"We'll now map out the right program for him to ensure he returns to the field in peak condition later in the year."

Haynes has played every game so far this season, averaging 19.3 disposals and 7.5 marks.