However, nothing came form these trials and Luntala has been training again with the Blues squad at Wast Hills.
Bruce said: "At the end of the season we decided it was best that Tresor looked elsewhere for another club. He knew his chances here were going to be limited.
"Unfortunately nothing worked out for him. Under the terms of his contract, there was a year's option that could have been taken up by either side - us or him.
"So he's decided to come back to us and will be another body available."
Luntala made just one appearance last season after Bruce took up the managers post at Blues and is still available should a suitable club come in for him.