The Black Cats paid £9m for the shot stopper from Hearts three seasons ago when Roy Keane was in charge at the Stadium of Light.
However, the former Scotland number one has struggled with injuries in the last two years and has lost his place to Simon Mignolet.
The 28-year-old's contract is due to expire at the end of the season and Bruce has admitted that a new deal is not currently in the offing.
"It’s a horrible dilemma that we face as a club, because we paid £9m for him, but he’s probably been injured for two of the three years that he’s been here," Bruce told a press conference.
"That’s a big problem for us. We hope he has the resilience to get back. I certainly think he has. If he gets himself back on the pitch, we can address the situation from there.
"At the moment, I really don’t think I can be starting contract negotiations. If I’m being honest with him, I’m not in that position yet and we won’t be until we see him back fit and raring to go."
Gordan has made 40 appearances for Scotland.