This paper considers a coupled system containing a van der Pol oscillator and a conservative system that admits a family of single-frequency oscillations: the oscillator affects the system by a weak one-way coupling (control). A control action implementing an orbitally asymptotically stable (in the large) cycle in the closed loop system is found. The stabilized oscillation in the controlled conservative system becomes the cycle’s projection onto the phase space of a Lagrangian system.