Coating systems for components of a gas turbine engine, such as a compressor casing, are provided. The coating system can include a ceramic material disposed along the compressor casing on a surface to be adjacent to a rotating compressor blade. The coating system is harder than the compressor blade and can reduce the rub ratio between the casing and blade. The coating system can thereby increase the lifetime of the compressor casing and blades. Methods are also provided for applying the coating system onto a compressor casing.