Have you heard of the Rule of Nine?

If you are a pitcher, catcher, or coach it is a concept that should be looked at to make your pitcher more effective. Let’s start by explaining what it means to apply the rule of nine. This is the mental or cognitive aspect of the game when calling pitches. It can take a .300 plus hitter and make then a .100 hitter. 

How does it work?

Your brain cannot adjust quickly enough to a change of 9 mph between pitches consistently. Knowing this can give the pitcher a great advantage. Every player and coach should understand the hitting zones. These zones are there to track strengths and weakness of hitters and how to pitch a given hitter depending on the batting average in each zone. The pitching zones are actually expanded beyond the typical hitting zones. Every zone has an actual and perceived velocity when the ball travels through the zone as it is picked up by the hitter’s eyes and interpreted by the brain. As an example, a golfer has 1 contact zone when striking a ball. A batter when applying this rule has 25 contact points/zones.

Figure: Perceived velocity of a 90 mph pitch in each of the hitting zones of a right handed batter.

Rule of nine hitting zones


A 90-mph pitch is interpreted differently by the brain given the location in each of these zones.

A pitch inside and high is perceived at a much higher velocity than a pitch down and outside. The hitter sees and interprets this information differently. The hitter’s time to effectively hit the pitch also changes. Effectively changing speeds can be achieved without changing pitches. The take home message is whether you are spot on with multiple pitches or struggling and locating 1 pitch you can still be competitive knowing this concept. Applying the Rule of nine can take an average pitcher and make him lights out. He will be able to increase out rates with less pitches thrown. I have personally applied this rule when calling pitches and as a whole consistently my teams ERA was 3 or less. 

If you have questions about pitching, baseball rehab, sports medicine, or want to make an appointment, contact Mike Ruppel at the Grafton location.

Freedom offers baseball specific rehab and training in Grafton and Brookfield, WI.

Physical Therapist at Freedom Physical Therapy Services
Physical therapist Mike Ruppel is a certified pitching instructor through the National Pitching Association and the Rod Dedeaux Research Baseball Institute out of USC. He also has a background in martial arts and enjoys treating and training athletes.