RedactedNarrative: Vessel #1 was following vessel #2 and heading northbound from the South Higgins Lake State Park area when vessel #2 let off of the throttle and coasted to a slow speed.  
  
  The operator of vessel #1 didn't see vessel #2 slow down and collided. The operator of vessel #2 was hit in the back by vessel #1.  Vessel #2 operator complained of back pain and was transported to Munson Health Care Grayling Hospital for treatment.