The strangest trade in baseball history occurred on March 4, 1973, when New York Yankees pitchers Mike Kekich and Fritz Peterson held separate news conferences during spring training. Their announcement: They had traded wives. And kids. And dogs.

"Actually, it was a husband trade -- Mike for me or me for Mike," Peterson told the Palm Beach Post in 2013.

The families had been friends since 1969. The actual "swap" occurred in the summer of 1972, then was made public in spring training. "It's a love story," Peterson said. "It wasn't anything dirty."

Even though Jim Bouton's "Ball Four" had been published in 1970 -- exposing many of the warts and off-the-field activities of players -- baseball was still slowly moving from its conservative, no-long-hair traditions into the Swinging Seventies.

"Mike started to campaign for my wife about in August," Peterson said at his 1973 news conference. "He talked to me seriously about it. He told his own wife, Susan, that he loved Marilyn more."

Kekich's relationship with Marilyn Peterson was already over by the time of the spring training news conferences, however. In the next day's New York Times, Murray Chass wrote of the two pitchers, "It was obvious they had bitter feelings toward each other."

Peterson was a big name -- an All-Star in 1970, when he won 20 games -- and was coming off a 17-win season. Kekich was a journeyman left-hander who had gone 10-13 in 1972, his best season. Coincidentally or not, both careers quickly tailed off after the wife swap. After averaging 264 innings the previous four seasons, Peterson went 8-15 and threw just 184 innings in 1973. The Yankees traded him during the 1974 season. Kekich made four poor starts with the Yankees and was traded to the Indians in June.

At the time, Peterson didn't think the exchange would be a national news story. "I saw my picture on TV when I woke up," he told the Palm Beach Post 40 years later. "And I said, 'Uh-oh, it's a big one.'"

For Peterson, the swap worked out. He's still married to the former Susan Kekich. While he claims he never read Bouton's book, the evangelical Christian wrote his own book in 2009, although Susan apparently wouldn't let him use her name, as he refers to her as his "new wife."

All these years later, the wife swap still holds interest. It's being made into a movie, produced by two guys named Ben Affleck and Matt Damon (although neither will star in it).

Peterson is a consultant on the project. Kekich, however, would apparently -- and understandably -- like to forget the whole episode. When news of the possible movie first leaked in 2011, reports said he had changed his identity and moved to New Mexico. "He isn't too keen on having the scandal dredged up again after all this time," a source told the New York Post's Page Six.