Develops for the first time an output-feedback universal controller that simultaneously solves global asymptotic stabilization and tracking of an underactuated omnidirectional intelligent navigator (ODIN), an underwater vehicle, in a horizontal plane with only position and orientation measurements available. A nonlinear passive observer is proposed to estimate unavailable velocity measurements. The control development is based on Lyapunov's direct method, backstepping technique and utilizes several physical properties of the underwater vehicle.