GUIDES · BETSLIP DOCTOR
Why is putaway percentage different from a pitcher's overall strikeout percentage?
Putaway percentage is conditional on two-strike pitches: it measures the rate of those pitches that result in a strikeout. Strikeout rate, or K%, is total strikeouts divided by total batters faced. One describes finishing pitches within a particular count situation; the other describes how often the pitcher strikes out batters overall. Their denominators differ, so the percentages are not interchangeable and should not be compared as if they were measuring the same opportunity.
For Bettors and cappers learning to read baseball records · Updated
Putaway percentage starts with two-strike pitches
MLB defines PutAway% as the rate of two-strike pitches that result in strikeouts. It can also be examined by pitch type to describe which offering finishes hitters in that two-strike context. The opportunity set is pitches thrown with two strikes, not every batter faced.
K% starts with batters faced
MLB defines strikeout rate as total strikeouts divided by total batters faced. It summarizes the pitcher’s strikeout frequency across plate appearances, not only pitches thrown after reaching two strikes. A pitcher can have different values for the two measures without any contradiction.
Check the pitch type and leaderboard sample separately
For a pitch-type comparison, verify which pitch is being counted and what minimum sample the current table requires. The MLB glossary’s example refers to a historical slider leaderboard and a stated 2018 minimum; that example is not a universal eligibility threshold for every season or pitch type. BSD does not claim to retrieve or display these Statcast rates.
Hypothetical worked example: two rates, two denominators
Toy season only—not a real pitcher. Suppose a pitcher faces 100 batters and strikes out 24, giving K% = 24 / 100 = 24%. In the same fictional sample, suppose 80 pitches are thrown with two strikes and 24 of those pitches end the plate appearance in a strikeout. PutAway% = 24 / 80 = 30%. The numerator matches here, but the denominators and questions differ: batters faced for K%, two-strike pitches for PutAway%. These invented counts are not an MLB leaderboard or forecast.
Related questions
Does a higher PutAway% mean the pitcher has a higher K%?
Not necessarily. PutAway% is conditional on two-strike pitches; K% uses all batters faced.
Is every two-strike pitch a separate opportunity?
The metric is defined over two-strike pitches that do or do not result in a strikeout. Check the source table’s exact filters when comparing a particular leaderboard.