Curveball
Also known as: curve, 12-6 curve, hammer, hook
The curveball is an off-speed breaking pitch with topspin that makes it arc downward, often dramatically, as it crosses the plate.
Thrown with a forward finger roll, the curveball generates topspin that causes the Magnus force to pull the ball down and, depending on arm angle, laterally. A 12-6 curve drops almost vertically; a 1-7 curve sweeps across more. Effective curveballs pair large movement with the appearance of a fastball out of the hand, then "fall off the table" as the batter commits. Command of the curveball — especially throwing it for strikes early in counts — separates good pitchers from great ones.
Example
He bounced a 78 mph curveball in the dirt and the hitter chased it for strike three, fooled by the fastball-like release.
Frequently asked questions
At what age should a pitcher start throwing a curveball?
Most youth sports medicine organisations recommend waiting until around 13–14 when the growth plates in the elbow are more developed. Mechanics and fastball command should come first.
Related terms
- SliderThe slider is a breaking ball with lateral movement and some downward tilt, faster than a curveball and typically sharper in its late break.
- Induced Vertical Break (IVB)Induced vertical break is the vertical movement a pitch achieves purely from spin, measured against a hypothetical spinless ball — isolating the Magnus effect from gravity.
- Pitch TunnelingPitch tunneling is the strategy of throwing different pitch types that share the same flight path early before diverging late — making it nearly impossible for the hitter to distinguish them in time.
- Pitching DeceptionPitching deception refers to any element of a pitcher's mechanics, grip, or delivery that delays or confuses the hitter's ability to identify the pitch type, speed, or location.
- Arm AngleArm angle is the vertical orientation of the throwing arm at release — from over-the-top through three-quarter, sidearm, to submarine — and it shapes both the pitch plane and movement profile.
- Release PointRelease point is the precise spatial location in front of the body where the pitcher lets go of the ball — consistency here is the foundation of command.
Related guides & benchmarks
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