The former Leeds United man had to be stretchered from the training ground and his injury has added to more problems for the Jets ahead of their knockout semi-final against Gold Coast United on Saturday night.
Bridges joins a long list of players in the treatment room for Branko Culina's side who confirmed the injury, saying it has caused 'disarray' at the club.
"We picked up a major injury at training today and that's further thrown the team selection into disarray," Culina said.
"If we do win, then it's going to be one hell of an achievement . . . any team that's missing their marquee player, their goalkeeper, their key striker and a few others would find it tough. But we won't give up.
"We'll have a couple of days off training and regroup, and fingers crossed we get at least some of them back this week.
"Our squad has always been pretty thin in depth," he said. "When we lose key players, it makes it tougher for everyone."