Performance of mechatronics systems can deteriorate significantly under the presence of delays in measurements. On the other hand, intentional introduction of a delay in a feedback control law may be beneficial in achieving good performance without relying on accurately tuned estimates for derivatives of measured signals. In this context, a proper design of retarded control laws represents an important challenge, and this paper gives a step forward to obtain better control laws for underactuated mechanical systems under the presence of time delays in measurements. Particularly, a Proportional-Retarded (PR) control law is designed for stabilization of an underactuated rotational inverted pendulum, known as the Furuta pendulum. Experiments over a laboratory platform as well as a comparison with a Linear Quadratic Regulator (LQR) are performed to show the advantages of the proposed scheme.