Boxing legend Ken Norton Sr., who has most noted in the boxing ring for his famous bouts with Muhammad Ali, passed away late Wednesday at age 70 of congestive heart failure.

Norton who battled illnesses from two strokes, prostate cancer and a heart attack, held a piece of the WBC Heavyweight Championship after his defeat of Ali in 1973 for a better part of five years. Ali defeated Norton in their next two bouts.

Norton hung up his gloves finally after losing to Gerry Cooney in 1981. He finished with a career record of 42-7-1 with 33 knockouts.

Ken Norton Sr., who also served in the U.S. Marines from 1963-67, is survived by two sons, one of whom is former NFL player and three-time Super Bowl champion Ken Norton Jr.