The electrosurgical instrument is configured to selectively perform ablation or coagulation as desired. The electrosurgical instrument includes at least two electrodes on the electrode probe that can be activated using an RF generator. The electrosurgical instrument is selectively switchable between an ablation mode and a coagulation mode by changing the amount of active surface area. In particular, in the ablation mode, a relatively small surface area is active. Thus, for a given power input, the current density is relatively high. In the coagulation mode, the active surface area is increased, thereby reducing the current density in the coagulation mode for the given power input.