At roughly midseason every year, Major League Baseball teams swap players, with floundering teams often dealing stars for prospects. No MLB trade deadline period, however, rocked the sports world quite like 1976.

Minutes before the trade deadline on June 15, Oakland A’s owner Charles O. Finley sold stars Joe Rudi and Rollie Fingers to the Boston Red Sox for $1 million each and Vida Blue to the New York Yankees for $1.5 million to prevent losing them for nothing in the sport's first free-agency period.

"Biggest sale of human flesh in the history of sports..." Ron Fimrite of Sports Illustrated called the deal, unprecedented in MLB history for stars and amount of money involved.

Three days after the sale, MLB commissioner Bowie Kuhn infuriated longtime nemesis Finley by voiding the transactions, citing his best-interests-of-baseball power. Finley's A's, a juggernaut in the 1970s, were crippled when Rudi, Fingers and other standouts left the team after the season in free agency because the owner couldn't afford them.

Since the advent of free agency—a ground-breaking right negotiated for players by MLB Players Association executive director Marvin Miller in late 1975—the sport has never been the same. Salaries skyrocketed and team-building became even more complex.

In April 1976, Finley began the dismantling of Oakland’s dynasty by trading star outfielder Reggie Jackson and pitcher Ken Holtzman to the Baltimore Orioles. His sale of stars in June angered fans of the A’s, the five-time defending American League West champions and World Series champs in 1972, 1973 and 1974.

“[Finley] can set up his cash on that [expletive] mound and come up here and cheer for his money,” an A’s fan at Oakland Coliseum told the San Francisco Examiner.

Other MLB owners were leery about the advent of full-fledged free agency, but none of them attempted to sell their stars as Finley had.

Deals involving star players and substantial sums of money were not new in MLB: In January 1920, future Hall of Famer Babe Ruth was sold by the Boston Red Sox to the New York Yankees for $125,000 and $300,000 in loans. Eighteen years later, pitcher Dizzy Dean, another future Hall of Famer, was sent by the St. Louis Cardinals to the Chicago Cubs for $185,000 and three players. In the early 1930s, Philadelphia A’s manager/owner Connie Mack sold future Hall of Famers Mickey Cochrane, Al Simmons and Lefty Grove.

Because the A’s were playing host to Boston when Finley sold them, Rudi and Fingers simply walked over to the Red Sox clubhouse to suit up for their next game. Before Kuhn ordered his return to Oakland, Fingers—who was inducted into the Baseball Hall of Fame in 1992—even had his picture taken in a Red Sox uniform on the field at Oakland Coliseum. But none of the three players in the sale played for his “new” team.

“If such transactions now and in the future were permitted, the door would be open wide to the buying of success by the more affluent clubs," the commissioner stated. "Public suspicion would be aroused. Traditional and sound methods of player development and acquisition would be undermined, and our efforts to preserve competitive balance would be greatly impaired.”

"Village idiot!” Finley called the dour Kuhn after his decision voiding the players' sale.

This 1976 mid-summer baseball circus, capped by Finley’s $10 million suit against the commissioner and MLB, served as fodder for days for the nation’s sports writers:

“It has taken the creation of Finley's First Annual Garage Sale, the passing of $3.5 million in small, unmarked bills and the appearance of coast-to-coast obituaries for his sport, but finally Kuhn has done something,” wrote Leigh Montville of the Boston Globe.

“Innovative, arrogant and, above all, flamboyant,” Kevin Lamb of the Chicago Daily News wrote of the attempted sales.

“It has been said of and by Charley Finley that he has a right to sell his ballplayers.” wrote Dick Young of the _New York Daily News. “_They are his property, and that is the American way, the capitalistic way. Not quite. When you join a men's club, or a country club, you agree to abide by its rules.”

Kuhn and Finley had a gasoline-meets-matchstick relationship for years: In 1972, the commissioner ordered the frugal Finley to re-open contract talks with Blue, who won the Cy Young Award as the American League’s best pitcher the previous season. During the 1973 World Series against the Mets, he demanded Finley reinstate infielder Mike Andrews, whom “Charley O” had released after he made two errors in a Game 2 loss.

With ace Blue, outfielder Rudi and relief pitcher Fingers back on the roster, the A’s finished second in the American League West in 1976. But, as Finley feared, Rudi (to the California Angels) and Fingers (San Diego Padres) left Oakland in free agency in the offseason. Blue lasted one more season with the A’s before he was traded to the San Francisco Giants. Oakland lost standout third baseman Sal Bando, catcher Gene Tenace and shortstop Bert Campeneris in free agency after the 1976 season as well, with Charley O getting nothing in return. The next season, the A's lost 98 games, and Oakland made only one playoff appearance from 1977-1987.

As for that $10 million lawsuit, Oakland manager Chuck Tanner was confident his boss would prevail. “You should own the American League after you get through with this one," he told Finley, according to the Oakland Tribune.

But Finley—who sold the A’s in 1980 and died in 1996—got nowhere in court. Ultimately, a U.S. Circuit Court of Appeals ruled in favor of Kuhn, who served as commissioner until 1984 and died in 2007. Charley O’s bitterness toward his antagonist lasted for years.

“All I can say is I think it’s a red-letter day for baseball,” Finley said after Kuhn announced his resignation.. “He drove me out of baseball …”