Curveball 101

For your regular curveballs, you jam the ball between your middle finger (usually on the seam) and your thumb. With a stiff wrist, most pitchers concentrate on pulling down on the ball to create the downward, vertical spin that makes a curveball drop.

Curveball Grips

Standard: Index finger rests lightly on the ball without applying pressure.

Crossover: Index finger crosses over and rest atop the middle finger.

Pointer: Index finger points straight up, so that it is not resting on top of the ball. 

Knuckle Curve: Commonly thought of as a different pitch, the knuckle-curve is merely a different placement of the index finger, in which the second-digit knuckle of the index finger rests on the ball. 

Slow motion example of a curveball in flight:

https://www.youtube.com/watch?v=-t52DKa6jcY

Al Leiter does a great job of explaining the basics of a really effective curveball. This is a must watch.

https://www.youtube.com/watch?v=Nl8W5j4MDc0

MLB pitcher Adam Wainwright does an awesome job explaining how he grips and throws his curveball.

https://www.youtube.com/watch?v=WD60we35aYA

Now you need to go out and practice this over and over and over. One great drill is throwing the ball into a bucket.