A protection device for a lower guide system of a fuel injector includes a debris shield deflecting a fuel flow around a lower guide system and a particle trap collecting particles contained within the fuel flow. By deflecting the fuel flow towards flow passages around the lower guide system, the particles contained in the fuel flow are prevented from entering a lower guide area, such as a radial gap between the stationary components of the lower guide system and the moving component of the valve assembly. The particle trap may be defined in a lower housing of the fuel injector or may be integrated in the debris shield. The debris shield may be integral with a valve assembly or may be a separate component. A permeable area may be integrated in the debris shield to enable partial flow therethrough.