It's a sad day in the world of boxing. Former heavyweight champion Ken Norton Sr.—who fought Muhammad Ali on three different occasions and infamously beat him during a match in 1973 when he broke Ali's jaw—passed away yesterday. His son Ken Norton Jr., who is a coach with the Seattle Seahawks, confirmed his father's death last night. Norton had reportedly suffered several strokes over the course of the last few years and had not been in good health.

Although Norton Sr. is probably most well-known for his fights against Ali, that's not all he accomplished during his storied boxing career. In 1978, he became the first boxer ever to become a heavyweight champion without having to take part in a heavyweight title match after heavyweight champion Leon Spinks chose to challenge Ali to a fight rather than give Norton a chance to fight for the belt. The World Boxing Council declared Norton a champion. Norton lost that title later that year during a match against Larry Holmes, but the bruising Norton/Holmes fight was a classic and is widely considered to be one of the best boxing matches of all time.

Norton continued fighting into the early 1980s, but his best years were behind him at that point. Still, thanks to the Ali fights and the Holmes fight, Norton had more than cemented his legacy in the world of boxing, and he later moved on to a career in acting and broadcasting. R.I.P. to a true champion.

[via ESPN Boxing]