By 1969 both the American and National leagues had expanded to twelve teams. The owners had by that time a clear sense of the importance of television to the future of their sport, and they were aware of the additional television audience that postseason play — restricted to the World Series until then — attracted. So they instituted a playoff season. Each league was divided into two divisions, and the division winners played one another in a five-game series to determine the pennant winner. Revenues aside, it was not a perfect system, as the New York Mets proved in 1973 by becoming arguably the worst team in history to almost win the World-Series. The Mets ended the season in a near three-way tie in the weak National League Eastern division, and only clinched the title on the last regular-season game. But the Mets had seventeen fewer wins than...