While running 7” casing in the hole, the injured person (roustabout) together with the derrickman were handling the hydraulic casing tong, to screw and tighten both joints. The derrickman was in charge of operating the hydraulic casing tong and the roustabout was in charge to open and close the casing tong around the casing. The roustabout had his left hand on the casing tong handle to guide the entrance of the jaw toward the casing joint. The derrickman pushed the casing tong to approach the casing. The effect of the weight and the movement of the casing tong resulted in the roustabout’s middle finger and first finger to be pinched between the casing and the power tong handle. The incident resulted in partially cutting off the first phalange of middle finger.