Two studies of pitch-tracking software have shown that MLB's strike zone has increased by almost 10 percent over the past five years, according to The New York Times.
Most of the increase is seen in an area just below the batter's knees on the lower part of the plate. From the Times:
[The strike zone] grew in each of the last five seasons and more in 2014 than in any previous season. Five years ago, pitches just below 21 inches high and over the plate were rarely called strikes. This season, they usually were, according to one of the analyses, by Jon Roegele, which appeared in the publication Hardball Times.
“The strike zone has increased in size significantly,” said Brian Mills, a professor of sports management at the University of Florida, and the author of the other analysis, “and it’s had a huge impact on run scoring over the past eight years or so.”
According to the report, the new, bigger strike zone more closely approximates how baseball's rule book defines the size of the zone, describing it as extending to "the hollow below the kneecap."
The move to the rulebook-defined zone could be a result of increased video review of umpires' performances. The review program was intensified before the 2010 season and umpires now receive reports on their performances after each game.
Several players told the Times that they have noticed the strike zone getting bigger in recent years, though several others said they believe any differences just stem from different umpires calling strikes differently.
The increased strike zone could be one of the factors in MLB's continued overall decrease in scoring, along with a prevalence in defensive shifts, increased specialization of pitchers and lower power numbers, which could be caused by increased testing for performance-enhancing drugs over the last decade.
Teams averaged 4.07 runs per game this season, down from the record of 5.14 runs in 2000.
The 2014 World Series features two teams with approximately league-average offenses. The San Francisco Giants scored 4.1 runs per game in the regular season, while the Kansas City Royals scored 4.02 runs per game.
- Ben Estes