Massa, who has penned a one-year contract with Baroka with the option of another year, will start training with the Absa Premiership newcomers tomorrow.
"It's done, the boy is mine now," club CEO Morgan Mamilla tells KickOff.com.
"Baroka and Celtic are working together now. [Our relationship] is more of [working] hand in hand when it comes to players. For Massa to come to us there was sort of a brotherhood agreement. He has signed for two years. It's one plus a one-year option but we are going to exercise the option."
He adds: "I'm looking more for hungry players. Massa is a hungry player when you compare him to other strikers. Now it's time for him to prove that he can play because he wasn't playing regularly at Celtic. He said he want to play and remember he is a captain of a national team. All the players are looking up to him. So it's a challenge for him but I think he will do well."
The National First Division champions announced 13 new signings last month and have also enlisted Orlando Pirates forward Siyanda Ngugo, who was on loan at Royal Eagles last season.
By Sipho Mlotha and Ernest Fakude