In sensor network applications, such as battlefield reconnaissance, disaster relief, and etc., the base stations may be disconnected from the sensor network. Several approaches assume that there exist particular nodes, mobile relays, in the network that are utilized to deliver messages to the base stations for dealing with the disconnection problem. The mobile relays collect messages from the source nodes and physically carry them to the base stations. However, these schemes are designed for delay-tolerant applications. This paper proposes that the mobile relays are exploited to move to designated positions, and to use transceivers with adjustable ranges to form forwarding paths between the sensor nodes and the base stations. The effectiveness of the proposed approach is evaluated in a series of numerical investigations using the ns-2 simulator. The simulation results indicate that the proposed scheme not only outperforms existing mobile relay methods in terms of the end-to-end delay and the energy consumption but also has similar message delivery ratio with existing methods.