Leslie Mann was an American athlete and sports administrator. He played college football and professional baseball, and went on to coach football, baseball, and basketball. He was the founder and first president of the International Baseball Federation (IBF), the predecessor to the modern World Baseball Softball Confederation (WBSC).

The International Baseball Federation (IBAF) is the former worldwide governing body of baseball. It has since been superseded by the World Baseball Softball Confederation (WBSC), and continues to exist as the WBSC's baseball division. Between 1944 and 1975, it was known by its Spanish-language name, as the Federación Internacional de Béisbol Amateur, or FIBA.