Employee was on overtime. EE stepped in a hole in the haul road injuring knee. EE did not seek treatment until 10/10. EE followed up with a Occupational Health Facility on 10/12 (next available appt.) & was granted a full release. EE worked the next two scheduled shifts. EE returned to the ER for re-evaluation on 10/14 & was place off work pending an MRI.