Employee was attempting to remove the keeper pin on a D-8 Cat blade with a 2 pound Sledge hammer and a punch. As EE swung the hammer, it glanced off of the punch, hitting EE in the left hand between the thumb and pointer finger. EE sought medical help on 4/13/16, but there were no fractures. EE returned to the doctor on 4/18/16 and was placed on light duty.