A coating system for a surface of a superalloy component is provided. The coating system includes a MCrAlY coating on the surface of the superalloy component, where M is Ni, Fe, Co, or a combination thereof. The MCrAlY coating generally has a higher chromium content than the superalloy component. The MCrAlY coating also includes a platinum-group metal aluminide diffusion layer. The MCrAlY coating includes Re, Ta, or a mixture thereof. Methods are also provided for forming a coating system on a surface of a superalloy component.