Strikeouts per game per team (by batters)

Last season, teams struck out at a rate never before seen: 7.5 times for each team every game, an increase of nearly 20 percent from 2005. Ten of the 30 major league teams set franchise records for strikeouts last season and most came close.

Strikeouts per game, 2012

Theories as to why hitters are striking out in ever-increasing numbers reflect changes in both pitching and hitting.

Barton Silverman/The New York Times (Soriano, Garcia); Richard Perry/The New York Times (Logan); Jason Szenes for The New York Times (Robertson) The Yankees frequently used four pitchers a game last season, the league average. Their most common four-man combination was Freddy Garcia, Boone Logan, David Robertson and Rafael Soriano.

Fresh Arms Keep Coming

The days of a starter going deep into a game and then giving way to his closer appear long gone. Managers now have extensive scouting reports of the opponent’s hitters against his pitchers. This has led to more specialization, more pitching changes — and more strikeouts. Hitters are now facing more fresh arms and ever-diminishing odds.

In 1924, the year with the fewest strikeouts, teams used a single pitcher nearly half of the time. Last season, the average was four per game.

Number of pitchers per team per game

Two Strikes, No Caution

Jonathan Ernst/Reuters

Bryce Harper, 2012 N.L. rookie of the year, hit .174 with two strikes, just below the league average. He was second among rookies in strikeouts with 120, including the one above against the Yankees.

Batting average by pitch count On pitches without 2 strikes (3-0, 3-1, 2-0, 2-1, 1-0, 1-1, 0-1, 0-0) On 2-strike pitch counts (0-2, 1-2, 2-2, 3-2)

Batting averages have declined for six straight seasons, largely because averages of hitters with two strikes are at the lowest point in the 25 years since the statistic has been kept.

Batting averages have remained fairly constant when a hitter has fewer than two strikes in the count...

... but batting averages of hitters with two strikes have fallen, as more hitters stay aggressive with two strikes instead of just trying to make contact. This is largely because home runs are often rewarded with more playing time and larger contracts.

Related article

Swing and a Mystery: Why Strikeout Rates Are Soaring

Theories abound on why baseball strikeouts have reached record highs, but with runs also climbing, does it matter?

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