A fuel injector assembly sufficiently configured to be mountable within an injector bore defined by a cylinder head assembly is provided. The fuel injector assembly includes an injector body having an injector tip portion and a generally annular combustion seal mounted with respect to the injector tip portion. A secondary combustion seal is mounted with respect to the injector tip portion and is substantially adjacent to the generally annular combustion seal. A cylinder head assembly incorporating the disclosed fuel injector assembly is also provided.