Bad news for fans who adore high-contact pests: Players punching out at Scutaro-esque levels are a dying breed. Strikeouts have spiked in the majors with the percentage of plate appearances ending in a K increasing from 17.5 in 2008 to 19.8 in 2012, highest in MLB history.
At this pace, poor umpire Jim Joyce is going to be hoarse by May.
What's behind the strikeout surge?
It appears that pitchers are fanning hitters by throwing more two-strike cutters and sliders in place of fastballs.
- In 2008, pitchers threw fastballs or sinkers 52.8% of the time in two-strike counts.
- In 2012, they threw fastballs 48.6% of the time in such situations.
- The percentage of two-strike curveballs and changeups thrown has remained about the same between 2008 and 2012.
- Pitchers are tossing considerably more cutters with two strikes (1.8% of two-strike pitches in 2008, and 5.5% in 2012) and sliders (19.4% in 2008, 20.7% in 2012).
As the table below shows, those cutters and sliders are driving the increase in Ks across the game.
The number of batters striking out on sliders has increased by about 22% from 2008 to 2012. Hitters struck out 342% more often against the cutter in 2012 than in 2008.
Increase in strikeouts by pitch type from 2008 to 2012
Here's another way of putting it:
- Cutters accounted for about 1.7% of total strikeouts in 2008, and 5.1% in 2012.
- Sliders made up 23.6% of total Ks in 2008, and 25.2% in 2012.
- Fastballs, meanwhile, have fallen from 45.3% of total strikeouts in 2008 to 41.9% in 2012.
Cutters and sliders are fueling MLB's strikeout surge, but in different ways. Pitchers are freezing hitters with two-strike cutters thrown over the plate. By contrast, batters are chasing -- and whiffing -- more often against sliders.
The increase in Ks via the cutter has come mostly from pitches taken in the strike zone.
In two-strike counts, pitchers threw a cutter over the plate 38.8% of the time in 2008. By 2012, they threw in-zone cutters in two-strike counts 43.2% of the time.
While pitchers are throwing more cutters in the strike zone, hitters have actually gotten worse at recognizing balls and strikes. Batters swung at two-strike cutters thrown in the strike zone 90.1% in 2008, but that decreased to 88.4% in 2012.
When pitchers go out of the zone, batters are chasing fewer cutters and making more contact when they do swing.
Cutters in two-strike counts
Pitchers are throwing about the same percentage of sliders over the plate in two-strike counts, and hitters are actually swinging at more strikes.
However, batters are chasing more two-strike sliders out of the zone (41.7% in 2008, 44.4% in 2012) and whiffing more often (45% in 2008, 48.4% in 2012):
Sliders in two-strike counts
- In two-strike counts, pitchers are throwing more cutters and sliders and fewer fastballs/sinkers.
- Those cutters and sliders accounted for a higher percentage of overall strikeouts in 2012 (about 30% combined) than in 2008 (about 25%), while fastballs/sinkers accounted for fewer Ks (about 45% in 2008, and 42% in 2012).
- Pitchers are throwing more two-strike cutters in the zone and batters are swinging at fewer of them, resulting in more looking strikeouts.
- Batters are chasing more two-strike sliders thrown out of the zone, and they're missing those pitches more often.