As a young man, Charles "Boss" Schmidt worked in the coal mines and developed a muscular and powerful physique. According to the Detroit Tigers information office, Schmidt beat Ty Cobb in several fights. In the second fight, Schmidt knocked Cobb unconscious but admired Cobb's resiliency while fighting and stayed to revive Cobb as he lay motionless on the Tiger dressing room floor. Despite their clashes, Schmidt and Cobb (both tough as nails) became close friends until Schmidt's death in 1932.
Schmidt also played a role in Cobb's March 1907 fist fight with an African American groundskeeper. When the groundskeeper tried to shake Cobb's hand, Cobb slapped him and chased him to the clubhouse. The groundskeeper's wife yelled at Cobb, and Cobb began to choke her. Schmidt intervened and stopped Cobb from hurting her further. Cobb and Schmidt then got into a fight and had to be separated by their teammates.
Schmidt was a skilled brawler who reportedly even fought an exhibition match with the heavyweight champion, Jack Johnson. He felt that he was the best fighting baseball player in the league and challenged all baseball players to a match.
Aside from his prowess as a fighter, Schmidt was also known for other displays of his physical toughness. As a catcher, Schmidt never wore shinguards. He could force nails into the floor with his bare fists. He once visited a local carnival with some of his teammates and wrestled and pinned a live bear. Schmidt's career was shortened due to numerous fractures sustained over the years of his thumb and fingers.
