THE INJURED WAS ASSISTING 2 OTHERS IN UNLOADING A TRACK IDLER FOR A CONTINUOUS MINER, THEY WERE TRANSFERRING IT FROM THE END OF THE MECHANIC'S MANTRIP INTO A SCOOP BUCKET WHEN THE IDLER ROLLED BACK CATCHING THE RING FINGER OF HIS LEFT HAND BETWEEN THE IDLER AND THE SIDE OF THE MANTRIP, RESULTING IN A LACERATION (4 SUTURES).