A combustor assembly in a gas turbine engine includes a gas generator casing, an annular combustor supported within the casing, and a fuel injection system that includes an internal fuel manifold assembly having a fuel manifold ring with at least one fuel conveying passage in fluid flow communication with fuel injection nozzles. An inlet member is connected to the manifold ring and includes a drainage passage for collecting possible leaked fuel that is defined between the inlet member and a heat shield surrounding the inlet member. Any leaked fuel is discharged out of the inlet member at an exit of the fuel passage on an end surface of the inlet member proximate the second end thereof.