GWS coach Leon Cameron has backed the decision to play Stephen Coniglio in Sunday's AFL match against Richmond, saying he had proved his readiness.
Coniglio did not last the opening five minutes of the MCG match before his heavily-strapped left knee gave away when he changed direction.
Two trainers had to help him from the field.
Cameron said post-match the club are unsure how seriously Coniglio is hurt.
Coniglio hurt his left knee in last week's loss to Brisbane, but Cameron noted he had trained during the week.
Cameron said it looked better than co-captain Callan Ward, who needed a season-ending knee reconstruction when he went down in the round-four win over Geelong.
"It's hard for me to give you an update yet," Cameron said.
"There's no doubt there are going to be people fearing the worst.
"I can't give you an answer yet - it's not like Callan Ward.
"It's clearly a lot more positive than that, but (we won't know) until we get it really, thoroughly checked out."
Cameron said the Giants sought widespread advice before passing Coniglio fit to play.
"Our doctors and physios and specialists around Sydney and also Melbourne were all saying he's ready to go," he said.
"The most important thing is Stephen saying he's ready to go.
"You're heading down the wrong path if you're trying to tie the two together."
Coniglio becomes a free agent at the end of this season and is one of the game's top onballers.
Richmond coach Damien Hardwick asked after him at the end of his post-game media conference.
"You always hate to see great players go down," Hardwick said.
"Hopefully he dodges a bullet there - good luck to him."
Australian Associated Press