Bruce feels Gordon will not have had enough time to overcome his knee trouble to begin the campaign and new signing Keiren Westwood is expected to start in goal.
With Belgian Simon Mignolet hoping to play an even greater role in the Premier League after proving his quality in his first year, Gordon will start as third choice.
That has alerted a number of clubs, particularly given that the Scotland international only has 12 months remaining on his contract and Sunderland are ready to consider offers for his services.
Celtic have expressed an interest in taking him back to the Scottish Premier League, but Manchester City and Arsenal are also interested.
Arsenal are on the look out for a goalkeeper after Arsene Wenger confirmed that Manuel Almunia can leave this summer, while City want a replacement for Shay Given, who is edging towards a move to Aston Villa.
Bruce admits the length of time remaining on Gordon's contract increased the uncertainty of his position.
The situation with Craig is he's got one year left on his contract, said Bruce. The big thing for Craig is to get him fit, that's the most important thing, to get him back on the pitch again.
Then let's deal with the problem, rather than panicking on a problem. It wouldn't be healthy if I hadn't brought a keeper in with Craig missing the start of the season.
What happened last year put us in a real mess. Simon did really well but it wasn't a healthy situation to be in. We've made sure we've done something about that.
Gordon underwent a knee operation towards the end of last season and has yet to resume training, which ultimately forced Bruce's hand to dip in to the transfer market and acquire Westwood on a Bosman after he left Coventry.
But the arrival of the former Carlisle shot-stopper, just 12 months after the signing of Mignolet suggested Bruce was looking to head in a different direction.
He said: I've signed Keiren to bring in competition and we saw what happened last year with Craig I don't think he's going to be ready until the end of August at least.
Pre-season will decide (who starts as first choice) but to be fair to big Simon, he's done nothing wrong. You need really good competition, and that's what pre-season's for, to decide who I'm going to choose.
Westwood is likely to be handed his first appearance in a Sunderland shirt at York City tomorrow night, when Bruce oversees the first friendly of the summer.
Craig Gardner and David Vaughan, two other signings, are also expected to figure, while the other six summer recruits are likely to be held back until the pre-season tour of Germany.
Wes Brown and John O'Shea are closest of the others to be involved at York, but it is likely they will also be asked to wait until Sunderland face Arminia Bielefeld on Sunday.
* Former Sunderland midfielder Sean Thornton is to join Metalist Khairkiv in the Ukraine.