Yes! I forgot!
From Wikipedia:
Major League Baseball has occasionally increased or reduced the size of the strike zone in an attempt to control the balance of power between pitchers and hitters. After the record home run year by Roger Maris in 1961, the major leagues increased the size of the strike zone from the top of the batter's shoulders to the bottom of his knees. In 1968, pitchers such as Denny McLain and Bob Gibson among others dominated hitters, producing 339 shutouts. Carl Yastrzemski would be the only American League hitter to finish the season with a batting average higher than .300. In the National League, Gibson posted a 1.12 earned run average, the lowest in 54 years, while Los Angeles Dodgers pitcher Don Drysdale threw a record 58 and two-thirds consecutive scoreless innings during the 1968 season. As a result of the dropping offensive statistics, Major League Baseball took steps to reduce the advantage held by pitchers by lowering the height of the pitcher's mound from 15 inches to 10 inches, and by reducing the size of the strike zone for the 1969 season.