Then 32, Flood was a three-time All-Star who had won seven consecutive Gold Glove awards in center field over a 12-year career. He had filed his suit challenging baseball's reserve clause in response to a trade that sent him from the Cardinals to the Phillies on Oct. 8, 1969.
Flood was the first witness to take the stand that day, describing his situation in detail under examination by his attorney, Arthur Goldberg, a former labor leader, Supreme Court Justice and UN ambassador who had been retained on Flood's behalf by the Major League Baseball Players Association, which was financing the suit.
"After 12 years in the Major Leagues. I do not feel that I am a piece of property to be bought and sold irrespective of my wishes," Flood had written in a letter dated Dec. 24, 1969, to Commissioner Bowie Kuhn, requesting the right to consider offers from other clubs.
When Kuhn denied his request for free agency, Flood sued him and Major League Baseball, charging that the reserve clause violated antitrust law as well as the 13th Amendment, which barred slavery and involuntary servitude.
Miller followed Flood to the stand on the first day and described the reserve system in baseball. Also testifying on Flood's behalf in the following days were Hall of Fame players Hank Greenberg and Jackie Robinson, as well as former pitcher Jim Brosnan.
"Anything that is one-sided in our society is wrong, and the reserve clause is one-sided in favor of the owners," said Robinson, the player who had broken baseball's "color barrier" in 1947. "It should be modified to give a player some control over his destiny."
Greenberg, who was considered the first Jewish superstar in American team sports and who went on to become a general manager and eventually part-owner of the Cleveland Indians, testified that the reserve clause hurt the game.
"My purpose in coming here is to point out that the reserve clause is obsolete, antiquated and definitely needs to be changed -- to cement relations between players and owners, and to improve baseball's image," Greenberg said.
"Times have changed, and baseball must go forward harmoniously, and the first step -- the last step -- would be to get rid of the clause. There is no reason baseball can't live without it."
As was widely expected, Judge Cooper ruled on Aug. 12, 1970, that antitrust laws did not apply to baseball due to earlier court decisions that provided an exemption to baseball.
"Existing and, as we see it, controlling law renders unnecessary any determination as to the fairness or reasonableness of this reserve system," Cooper wrote in his 47-page decision.
Flood and the Players Association appealed their case to the Second Circuit Court of Appeals, which they considered a stepping stone to having the Supreme Court reconsider baseball's longstanding antitrust exemption.
After Cooper's decision was affirmed by the second circuit, it was appealed to the Supreme Court, where Flood ultimately lost, 5-3, in a highly controversial decision written by Justice Harry Blackmun that conceded baseball's antitrust exemption was "an anomaly."
Flood's courageous effort nonetheless heightened awareness among his fellow players and the public about the basic unfairness of the reserve clause, setting the stage for the Players Association's successful arbitration case against it in 1975.