June 15, 1977: Tom Seaver, Mets to Reds
It was one of the darkest days in New York sports history when the Mets traded ace Tom Seaver—a pitcher so central to the team that one of his nicknames was "The Franchise"—to the Reds for four young and mostly forgettable players, namely pitcher Pat Zachary, infielder Doug Flynn and outfielders Dan Norman and Steve Henderson. The move was keyed by a salary dispute with Mets board chairman M. Donald Grant (acting on behalf of owner Lorinda de Roulet) and a war of words with New York Daily News columnist Dick Young, and it came just as the trade deadline—which wasn't moved to July 31 until 1986—was approaching. A trade sending a three-time Cy Young winner and ace of the 1969 Miracle Mets to the two-time defending world champions was so momentous that it landed the cover of SI; Larry Keith's story carried the immortal headline, "Tom Terrific Arms The Red Arsenal."
Though Tom was in fact terrific for Cincinnati, going 14-3 with a 2.34 ERA, the Reds finished second in the NL West. Seaver spent another 9 1/2 years in the majors, and even returned to the Mets in 1983. While he did not add another championship to his mantel, he helped Cincinnati to the NL West title in 1979 and finished second in the Cy Young voting behind Fernando Valenzuela in 1981. He finished with 311 wins and was elected to the Hall of Fame in 1992 with 98.8% of the vote, a record that stood until it was surpassed by another player on this list, Ken Griffey Jr., in 2016.