GWS vice-captain Stephen Coniglio will miss six weeks with a syndesmosis injury.
The midfielder suffered the high ankle sprain in the third quarter of the Giants’ win over North Melbourne at Manuka Oval on Friday night.
GWS Head of Athletic Performance said it was a tough setback for Coniglio.
“We’re obviously disappointed for Stephen after he put in a really strong pre-season,” Joyce said.
“He’ll spend the next two weeks in a protective boot and progress from there.
“We’re confident that with the right treatment he’ll be back on the field in a bit over a month.”
GWS play their first game of the 2017 season against Adelaide at Adelaide Oval next Sunday.