On December 15, 1974, Oakland’s Jim “Catfish” Hunter is ruled a free agent by arbitrator Peter Seitz—the first free agent in modern baseball history—after A’s owner Charles O. Finley fails to live up to terms of the star pitcher’s contract. “The contract is quite clear as to what Finley is obligated to do, and it is also clear he has done none of it,” Marvin Miller, head of the powerful Major League Baseball Players Association, tells reporters.

Hunter helped the Oakland A’s win World Series championships in 1972, 1973 and 1974. He won the Cy Young Award as the American League’s best pitcher in 1974. But that winter, he was unhappy with the A’s, particularly Finley.

The arbitrator’s decision left Hunter in limbo.

“I hung up the phone, turned to my wife and said, ‘We don’t belong to anybody,'” he said years later to the Los Angeles Times. “I was scared. I didn’t have a job. I didn’t realize the implications.”

After fielding offers from many other teams, Hunter signed with the New York Yankees for five years and $3.75 million. He played five seasons in New York, winning two World Series. 

Finley, an innovative mind but not universally liked by players, had a simple philosophy when it came to running the A’s. “We run our club like a pawn shop—we buy, we sell, we trade,” the Times quoted him as saying. But his philosophy eventually led to the decline of his once-powerful team.

Hunter, who was elected to the Baseball Hall of Fame in 1987, died in 1999.

In December 1975, MLB pitchers Dave McNally (Montreal Expos) and Andy Messersmith (Los Angeles Dodgers) were also declared free agents by Seitz, another seismic event in MLB history. The move effectively ended the reserve clause, which bound players to teams, and led to the first free-agent player draft on November 4, 1976.

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