Curt Flood was a dazzling center fielder for the St. Louis Cardinals when, in 1969, he was traded to the Philadelphia Phillies. But instead of accepting his fate, Flood shocked baseball by suing the sport over its Reserve Clause, an age-old rule that bound players to their teams in perpetuity. His extraordinary case went all the way to the Supreme Court and helped pave the way for major advancements in the rights of professional athletes. This is...