The ex-anchorman slammed Kai Havertz for his performances up front with Germany.
Havertz may be used as the no.9 by the Germans at Euro 2024 at home this summer.
Hamann told Prime Casino: "Havertz, he is not a centre forward. He had a decent end to the season, but for me he still flatters to deceive most of the time. I think he's capable of so much more.
"Is he the presence up there that will score the goals for Germany and get us deep into the tournament? I'm not sure that he is. Versatility is good, but he’s at that stage of his career where he needs to define his role.
"If you asked a hundred people what his best position is, you would probably get a lot of different answers. He's not a centre forward, but he's not prolific enough to score goals or create chances as an offensive midfielder."