In the current literature of control systems design, there are numerous techniques and approaches have been developed to achieve regulation and tracking, with prescribed requirements of stability, performance and robustness. On the one hand, the problem of Output Regulation (OR) refers to the design of a control system able to achieve asymptotic tracking of prescribed trajectories and asymptotic rejection of disturbances, in a robust way, both generated by an autonomous system called exosystem. On the other hand, Model Reference Adaptive Control (MRAC) is one of the main design approaches in adaptive control, where the goal is that of tracking time-varying bounded references under parametric model uncertainties.