Illegal Pitches in Baseball: History, Rules, and Impact on the Game

Pat Bloom

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Illegal Pitches in Baseball

Ever wondered what makes a pitch illegal in baseball? Whether you’re a seasoned fan or new to the game, understanding the nuances of an illegal pitch can deepen your appreciation for America’s pastime.

An illegal pitch occurs when a pitcher violates specific rules, such as delivering a pitch without having their pivot foot in contact with the rubber or making a quick return pitch.

When an illegal pitch is called, the consequences vary depending on the game situation. With runners on base, it results in a balk, advancing the runners.

If no runners are on base, it’s simply called a ball unless the batter swings and reaches first base, in which case the play stands. Knowing these details can elevate your game-watching experience and give you a new perspective on the strategies at play.

Exploring Illegal Pitches in Baseball

Understanding illegal pitches in baseball is essential for appreciating the game’s dynamics fully. Here’s a condensed version of your detailed overview:

Definition and Overview

An illegal pitch occurs when a pitcher breaks specific rules during their delivery to the batter. These violations include delivering the pitch with their pivot foot not in contact with the rubber or making a quick return pitch.

When ruled an illegal pitch, it results in a balk if runners are on base or a ball if no runners are present, provided the batter does not swing. This rule aims to ensure fairness and maintain the game’s integrity.

The History of Pitching Rules

Pitching rules have evolved to manage various tactics employed by players, such as the spitball, where pitchers altered the ball’s surface with substances like saliva or petroleum jelly.

Popularized by players like Ed Walsh in the early 20th century, this technique created pitches with unpredictable movement.

Major League Baseball banned the spitball in 1920, although existing pitchers were grandfathered in. These rule changes demonstrate the league’s dedication to maintaining fair play and competitive balance.

Common Types of Illegal Pitches

In the dynamic interaction between pitcher and batter in baseball, certain pitches are considered unfair and against the rules. These illegal pitches, though often clever in design, compromise the sport’s integrity. Here are some common types:

The Spitball

The spitball is an illegal baseball pitch where the pitcher alters the ball’s surface with substances like saliva. It dates back to the late 19th century and gained prominence with pitchers like Ed Walsh in the early 1900s.

By making the ball’s surface unpredictable, it became difficult for batters to hit. In 1920, MLB partially banned the spitball but allowed a few pitchers, such as Burleigh Grimes and Red Faber, to continue using it until they retired as part of a legacy agreement.

The Quick Pitch

A quick pitch occurs when a pitcher delivers the ball to the batter before the batter is adequately set in the batter’s box. This tactic deceives, rushes, or surprises the batter, creating an unfair advantage.

According to MLB rules, a quick pitch is illegal and can result in a ball if there are no runners on base or a balk if runners are present. The rule ensures that the batter has a fair chance to prepare for each pitch, maintaining the integrity of the competition.

Consequences of Using Illegal Pitches

In the intricate world of baseball, where the balance between offense and defense is delicately maintained, the use of illegal pitches carries significant repercussions. Pitchers who resort to such tactics not only risk the integrity of the game but also face severe penalties.

Here are the consequences of using illegal pitches:

Penalties for Pitchers

In baseball, illegal pitches, such as those involving foreign substances like petroleum jelly or pine tar, lead to strict penalties. Umpires can remove pitchers from the game if these substances are detected on the pitcher, glove, or ball.

According to Rule 6.02(c)(7), even possession of a foreign substance is punishable, with first offenses receiving a warning and repeated infractions leading to ejection and suspensions, as seen in Jay Howell’s case in 1988.

Pitchers spitting on the ball, violating Rule 6.02(c)(2), face similar penalties, including the removal of the ball and illegal pitch calls, with continued violations resulting in suspensions, fines, and damage to a player’s reputation.

Impact on Game Integrity

Illegal pitches compromise baseball’s integrity by using substances like Vaseline or pine tar to alter the ball’s flight, giving pitchers unfair advantages. This disrupts the balance of the game and erodes public trust in fair play.

The banned spitball, made popular by Ed Walsh, exemplifies how such tactics can make hitting difficult. Players caught cheating face long-term stigma and loss of respect, impacting their careers and sportsmanship.

MLB enforces rules against illegal pitches to keep the sport fair and competitive.

How Illegal Pitches Are Identified?

Identifying illegal pitches in baseball requires a combination of keen observation, adherence to rules, and sometimes the aid of advanced technology. Here’s how umpires and officials spot rule violations:

Role of Umpires

Umpires play a crucial role in identifying illegal pitches during a baseball game. They observe the pitcher’s actions and are vigilant about any irregularities that might indicate tampering with the ball.

If they suspect a pitcher has altered the ball or used a foreign substance, they can inspect the ball and the pitcher immediately. Umpires have the authority to eject a pitcher from the game if they find any rule violations, maintaining the integrity of the sport.

Monitoring and Enforcement Technologies

With advancements in technology, identifying illegal pitches has become more sophisticated. High-speed cameras and real-time analytics are used to monitor pitches more closely than ever before.

These technologies can detect unusual ball movement or unexpected changes in spin rate, which might indicate the use of foreign substances. Data from these tools informs umpires and league officials, helping them enforce rules more effectively.

Touching Mouth or Lips

Pitchers often touch their mouth or lips to gain a better grip on the ball, but this can lead to suspicions of illegal pitches. To avoid this, pitchers must wipe their hand before contacting the ball if they’ve touched their mouth.

Umpires monitor these actions closely, and failure to follow this protocol might result in a warning or more severe consequences. This rule ensures the pitcher doesn’t introduce any foreign substance to the ball, even inadvertently.

Spitting on the Ball

Spitting on the ball alters its surface and creates an unfair advantage for the pitcher. Umpires watch for this practice and act swiftly if detected. A spitball can change the ball’s trajectory in a way that’s hard for the batter to predict, disrupting fair play.

If a pitcher is caught spitting on the ball, they face immediate penalties, including possible ejection from the game. Regular checks and vigilance by the umpiring crew are essential to prevent such violations.

Frequently Asked Questions

Why are spitballs considered illegal in baseball?

Spitballs are illegal because they alter the natural movement of the ball, giving the pitcher an unfair advantage. MLB banned spitballs to maintain fair play and ensure the integrity of the game.

What is a quick pitch, and why is it illegal?

A quick pitch occurs when the pitcher delivers the ball before the batter is set and ready. It is illegal because it is deceptive and can pose safety risks to the batter.

How do umpires identify illegal pitches?

Umpires identify illegal pitches by closely monitoring pitchers’ actions, such as touching their mouth or spitting on the ball. They also use technology like high-speed cameras to ensure compliance with the rules and maintain game integrity.

How does MLB ensure fair play regarding illegal pitches?

MLB employs strict rules and uses advanced technologies to monitor and enforce pitching regulations. Umpires are trained to spot violations promptly, and severe penalties are imposed to deter rule-breaking and uphold fair play.

Can a pitcher be ejected for using a foreign substance?

Yes, a pitcher can be immediately ejected from the game if caught using a foreign substance on the ball. This rule helps preserve the integrity and fairness of the sport.


Understanding illegal pitches in baseball is crucial for maintaining the sport’s integrity. Umpires and advanced technology play pivotal roles in identifying and preventing rule violations.

By staying informed about these regulations you’re supporting fair play and ensuring that the game remains enjoyable for everyone.

Remember the importance of adhering to the rules and the significant impact it has on player reputation and the overall quality of the sport. Embrace the spirit of fair competition and appreciate the vigilance required to keep baseball honest and exciting.

Ensuring that players and coaches stay educated about illegal pitches helps preserve the essence of the game. Continuous learning and strict enforcement underline that baseball is not only a pastime but a disciplined sport where integrity prevails.

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Pat Bloom

I lead Washington University in St. Louis' baseball team, emphasizing skill development, strategic play, and sportsmanship. Our rigorous training and competitive spirit cultivate discipline and teamwork, preparing athletes for success both in baseball and academics. We embody the determination and sportsmanship that define our university's athletics. LinkedIn

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