So far as numbers go, you could argue that Bill Romanowski isn’t one of the worst players to ever win a Super Bowl. His stats aren’t mind-blowing, but he was a two-time Pro Bowl selection. In terms of conduct, however, Romanowski is generally seen as one of the most toxic and dirty players in NFL history. Romanowski was fined and expelled several times for doing things like kicking players in the head and trying to break their fingers. He also crushed the eye socket of one of his teammates during practice.
Through it all, he won four Super Bowls. Following his retirement, he wrote an autobiography and founded a nutritional supplement company (Nutrition 53). He served as a high school defensive coordinator and later admitted to using steroids during his career.