Bent has had a hamstring niggle for a few weeks and his manager feared the worst when he limped off the Stadium of Light pitch after last Saturday's victory over Arsenal.
But after being told the results of a scan he had on Monday were favourable, Bruce is ready to keep the England international in his starting line-up at Wigan tomorrow.
The £10.5m man, whose nine goals this season have been instrumental in Sunderland's rise to eighth in the Premier League, trained yesterday for the first time this week.
Bruce said: If it was just a cut or a knock that would be one thing but he's obviously felt something.
We think it was more cramp and fatigue and the muscle tightening up.
We've been very thorough in the scans and all the stuff that can be. With a hamstring injury he wouldn't be bounding around like he was on Thursday if he'd nicked it.
We'll see how he is on Friday.
But it gave everyone a huge lift to see him on the training ground, that's for sure.
He did his work with the physios and it was pretty vigorous.
It wasn't half-paced or anything like that and he was flying.'' Bent's injury boost has given Bruce the perfect lift ahead of his return to former club Wigan tomorrow, particularly after he was criticised by outspoken Latics owner Dave Whelan this week.
Despite leading Wigan to 11th last season, their highest top-flight finish, Whelan claimed Bruce left his successor, Roberto Martinez, with a number of dodgy signings in the wake of last Sunday's 9-1 drubbing at Tottenham.
Bruce, however, is unconcerned and still has an enormous amount of respect for the club's owner, who has taken them from League Two to the Premier League during his time in control.
Dave was on a beach in Barbados, he'd probably had had a game of golf and was drinking the rum, a few too many over lunch, said Bruce.
He deflected the result very well. It was very clever taking the heat off Roberto and putting it on to me.
I said for 12 months, January to January, we amassed 60 odd points. It was the best team I have ever had but unfortunately it broke up very quickly.
Antonio Valencia's deal with Man United was done last Christmas. It was difficult to replace that sort of talent.
The big problem was keeping the squad together. We lost Emile Heskey and Amr Zaki went AWOL. We lost Wilson Palacios to Tottenham and the Valencia deal was almost done.
If we had kept them we would have been top ten and with an outside chance of Europe.
I always said it would be great to see Wigan on Easyjet.
The owner was sensible enough to know they had to have that policy. He knew the club's limitations.
Bruce is expecting a different Wigan performance to that which surrendered so cheaply at Tottenham, where they were just a goal behind at half-time.
And so is his opposite number Martinez. The Spaniard said: The players need to have the mental strength to cope with that disappointment.
But we will be ready and if we had the choice of playing today or Saturday we would choose today, to rectify things.
The game could be a real turning point for us. When you look at the bigger picture it was just a defeat and three points lost.
The manner of the defeat is something we need to back from.