AdvancedPitching · Tracking
VAA
Vertical Approach Angle
The downward angle of a pitch as it reaches home plate. The closer to 0°, the flatter it comes in.
−4.9°MLB average for four-seamers (about −4.8 to −5.0°)
Simple explanation
Almost every pitch is still falling when it arrives, so the number is negative, and −4° is “flatter” than −6°.
High in the zone, a flat four-seamer stays above the path the hitter is expecting. The bat passes under the ball, so whiffs and pop-ups go up.
Benchmarks
- −5.5°
- Steep
- −4.0°
- Flat
- −3.5°
- Very flat
Four-seamers only. Pitch height moves the angle a lot, so only compare pitches thrown at similar heights.
Detailed explanation
Throw a pitch higher and its angle gets flatter naturally. For comparing pitchers, people use a VAA adjusted for pitch height. Without it, anyone who just pitches high a lot gets more credit than he deserves.
A flat angle comes from a low release height, long extension, high velocity and plenty of induced vertical break (IVB). A shorter pitcher or one with a low arm slot can have a high fastball that plays much better than you'd guess.
Pitches built to drop, like curveballs and sinkers, are the opposite case. A steep angle is what makes them work, so flatter isn't always better.