SAG MILL MAINTENANCE. EE WAS EXTRACTING THE LIFTER BAR FROM THE WEAR PLATE & IT ROLLED OFF THE BOLT, FALLING AGAINST HIS LEG & CAUSING A DEEP CONTUSION. EE RTW NEXT NIGHT, WORKED SEVERAL HOURS BEFORE COMPLAINING OF PAIN & GOING HOME. HE CALLED OFF SHIFT 5/14 & SAW PERSONAL PHYSICIAN ON 5/16. RECOMMENDED STAY OFF LEG APPROX. 4 DAYS. AS OF 5/26 NOT RELEASED TO RTW.