Second deadball era
From BR Bullpen
The Second deadball era was a period of time, from roughly 1964 to 1972, when batting averages were unusually low in major league baseball. Some observers would extend the time period as far as 1963-76.
The first deadball era had lasted from roughly 1901 to 1919, and many fans were not quite able to understand why players in that era didn't hit as well as the ones from the 1890s. In the same way, fans were not quite clear as to why players in 1968 hit for batting averages much lower than players from previous decades. There were always many fans, and some ex-players, who maintained that the players from 1964 to 1972 just weren't as good as the previous ones, even though many of the players in the 1960s had also played in the 1950s.
It is also possible that the quality of pitching in this era was exceptionally strong -- a number of great older pitchers were winding up their careers (Sandy Koufax, Don Drysdale), while a number of other great pitchers were still in their prime (Jim Bunning, Juan Marichal, Bob Gibson), while a new generation was emerging (Don Sutton, Steve Carlton, Tom Seaver, Bert Blyleven, Ferguson Jenkins, Phil Niekro, Catfish Hunter, Jim Palmer, Nolan Ryan). At a level just below this roster, one encounters the names of many other near-great pitchers. One need look not only at wins and losses and earned run averages but at the number of complete games to appreciate the depth and strength of the pitching of ths era. Many of these pitchers continued to dominate the game for years after the close of the second deadball era.
Such a theory ignores the fact that scoring fell across baseball and that a few exceptional pitchers will not have such a significant ripple effect across Organized ball. Additionally, complete games are easier to accumulate in an era of low scoring, as pitch counts per inning will be less and a pitcher's arm will be in better shape in the late frames.
During the 1960's, many other explanations were given for the "decline" in hitting, including the existence of several new ballparks, the expansion of teams (first to 10 teams and later to 12 teams in the same decade) and the slow pace of games.
 Impact on the American League hitters
The American League was affected more deeply than the National League. Just prior to the second deadball era, the American League as a whole had been hitting around .255 (in 1960-62). Starting in 1963, though, the league was unable to hit better than .250 for eleven years (it managed to get up to .250 exactly in 1970). The worst year was 1968, when the league as a whole hit .230. The league had also hit under .240 in 1967 and 1972.
From 1962 to 1972 in the American League, no batting champ hit higher than .337 (and only two hit as high as .330).
The American League climbed out of the hole in 1973, when it hit .259, and continued to hit .255 or better for several years, and then hit .266 in 1977.
The previous year, 1967, had been even worse in one sense - the 10th best batter in the league, Don Mincher, hit only .273.
As a comparison, the American League as a whole in 2000 hit .276.
If one chooses to look at Runs/Game (per team), the American League dropped from about 4.5 Runs/Game before the era down to around 3.5 Runs/Game in the depths of the era.
 Impact on the National League hitters
The National League batting averages started at a somewhat higher level and did not drop as far. The NL had hit over .260 in 1961 and 1962, and so the drop was mainly into the .240s. Between 1962 and 1963 there was a sixteen point drop in the league batting average. It would be 1977 before the National League again hit over .260.
The worst year for the National League was also 1968, when .291 would get you on the list of the top ten batters in the league. That .291 average belonged to Roberto Clemente, one of the highest average hitters of the second deadball era, and it was the only year from 1960 to 1972 when he would hit under .312.
 Impact on pitchers
As one might imagine, the ERAs of the pitchers dropped along with the batting averages of the hitters.
In the American League in 1968, the overall ERA was 2.98, with the best team ERA being 2.66 (a tie between the Baltimore Orioles and the Cleveland Indians). It was a year in which Tommy John had a 1.98 ERA - and was only fifth in the league.
1972 wasn't quite as bad a year in the American League, as a 2.08 would be good enough for fifth in the league. Things were much better in the National League, where Don Sutton's 2.08 ERA put him third in the league.
 The end of the second deadball era
By 1977, things were definitely back to normal, as only one pitcher in all the major leagues, John Candelaria, had an ERA under 2.50. Rod Carew flirted with hitting .400 much of the year, and in both leagues it was necessary to hit around .310 in order to have a chance to be in the top ten in the league.
 Further Reading
- Paul Hensler: "A Farewell to Arms: The Major Leagues in 1968 and the Transition to a New Modern Era", in The Baseball Research Journal, SABR, Volume 37, 2008, pp. 101-104.