The 31-year-old Zimbabwe international spent the second half of the season on loan at the Stadium of Light from Manchester City but did not find the back of the net once during his time there.
Benjani is now deemed surplus to requirements at Eastlands, but Bruce has revealed he will not seek to make a permanent move for the powerful forward.
"Benjani was a good loan signing for us at the time because we needed cover in case of injuries," he said.
"In the end, he didn't play many games, but the extra competition brought the best out of the other lads.
"I think Kenwyne Jones, in particular, could see that Benjani was most likely to take his place and rose to the challenge."
Benjani moved to City for £3.5million in 2008 from Portsmouth and is now set to search for a new club during the transfer window.