The flag of Pittsburgh is colored with black and gold, based on the colors of William Pitt's coat of arms; Pittsburgh is the only city in the United States in which all professional sporting teams share the same colors. The city's first National Hockey League (NHL) franchise, the Pittsburgh Pirates were the first to wear black and gold as their colors. The colors were adopted by founder of the Pittsburgh Steelers, Art Rooney, in 1933. In 1948, the Pittsburgh baseball Pirates switched their colors from red and blue to black and gold. Pittsburgh's second NHL franchise, the Pittsburgh Penguins, wore blue and white, due to then-general manager Jack Riley's upbringing in Ontario. In 1979, after the Steelers and Pirates had each won their respective league championships, the Penguins altered their color scheme to match, despite objections from the Boston Bruins.[3][4]