In this paper we consider the output tracking problem of an uncertain nonlinear system under the action of an inverse control thus making a robustifying feedback component necessary. Conventionally, the robustifying control is designed taking into account an operating point. We present a nonlinear robustifying controller for tracking any trajectories inside its stability range. The design procedure of this nonlinear controller is based on a simple extension of a stabilizing H2 or H-inf controller. If su±cient conditions are satisfied, robustness in terms of the L2 gain from the disturbance input to the tracking error performance variable can be guaranteed and calculated a priori. Finally simulation results verify the proposed method.