A boat fender system and a method for deploying a cylindrical fender. The system includes a U-shaped member having a spindle on which is rotatably mounted a fender, and a lateral arm portion which is detachably connected to a locking assembly attached to a boat. The method includes mounting the fender to be freely rotatable about its longitudinal axis, and maintaining the fender in a vertical orientation and in a fixed position relative to the boat so that the fender comes into rolling contact with both the boat and a mooring structure.