The present invention relates to a method for treatment of at least one metallic surface of a substrate comprising at least a step of contacting said surface with an acidic aqueous composition (A), said acidic aqueous composition (A) comprising (a) one or more metal ions selected from the group of titanium, zirconium and hafnium ions (b) and one or more polymers (P) containing OH- and/or COOH-groups as well as at least one sulfur-containing moiety, to a corresponding acidic aqueous composition (A) as such, to a master batch to produce such acidic aqueous composition (A), to the use of the acidic aqueous composition (A) for treating metallic surfaces and to substrates comprising the thus treated surfaces.