Emp claimed inj back on Fri. 7/28 but did not report it until Mon. 7/31. Emp was oper. a Komatsu 400HM haul truck and hit a pothole in the haul rd. causing inj to lower back. This report was originally submitted via paper copy, and this report is being generated to make amendments per MSHA field office. Original was submitted 8/8/17.