On August 4, 2017, Toronto Blue Jays reliever Mike Bolsinger gave up four runs in one-third of an inning against the Houston Astros. “It was like they knew what I was throwing,” he later recalled. It would be his final major league appearance.
Two years later, the world learned why. The Astros had been using a video camera to steal signs, banging on a trash can 54 times during that game—12 times while Bolsinger pitched. When former Astros pitcher Mike Fiers revealed the scheme to The Athletic in November 2019, it exposed baseball’s vulnerability to technological cheating.
The scandal’s aftermath would reshape the sport through innovation. Today, sophisticated communication devices are changing how baseball is played at every level.
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From Scandal To Solution
Major League Baseball approved the use of PitchCom devices before the 2022 season with the dual intentions of deterring sign stealing and quickening the pace of play. The timing wasn’t coincidental. The Houston scandal had exposed fundamental flaws in baseball’s century-old communication system, where catchers used finger signals to call pitches—signals that could be stolen by observant opponents.
PitchCom eliminates the need for a catcher’s traditional finger signals. Rather, the catcher wears a forearm sleeve resembling a remote control with nine buttons for calling the pitch and location. When buttons are pressed, encrypted audio instructions are transmitted instantly to receivers worn by the pitcher, catcher, and up to three fielders.
The technology itself has an unlikely origin story. PitchCom is the creation of ProMystic, a modular technology company that typically caters to mentalists and magicians. ProMystic approached MLB with its idea for a pitch signal communication device in 2020, recognizing an opportunity to apply their expertise in covert communication to baseball’s sign-stealing problem.
The Mechanics Of Modern Communication
The system’s operation is deceptively simple. Catchers put a PitchCom transmitter on their forearm, which makes it look just like a wristband. The black transmitter has nine buttons that catchers press to let the pitcher know the pitch he’s calling and the location. On the mound, pitchers have a six-inch rubber receiver inside their hats that communicate the pitch call with a computerized voice—either in Spanish or English—that will tell the pitcher, for instance, “fastball up” or “curveball, down and in”.
MLB is providing each team with three transmitters, 10 receivers, and a charging case for the PitchCom Pitcher Catcher Communication Device. It is available in English and Spanish. The league has also established strict protocols: signals communicated via PitchCom may only be given by the catcher in the game. Signals may not be sent from the dugout, bullpen, a different player in the field, or anywhere else.
The early adoption wasn’t without challenges. Early in the 2022 season, New York Yankees pitcher Aroldis Chapman had difficulty hearing PitchCom over the crowd during an appearance at Oriole Park at Camden Yards. During the 2022 season, in response to complaints, PitchCom was modified to have a higher volume limit and to have an extension tube that put sound closer to the player’s ear.
Measurable Impact On Game Flow
The technology’s effect on baseball’s pace has been significant. Across the majors, the average time of a nine-inning game in 2022 decreased by six minutes from the prior season, which ESPN credited in part to PitchCom. Individual teams saw even more dramatic improvements: Through their first 54 games in 2022, the Yankees played 25 games (almost half) in less than three hours each. In 2021, only about one quarter of the Yankees’ games finished in three hours or less.
The speed improvements stem from eliminating traditional sign complications. Things grind to a halt because there’s a real cat-and-mouse game—with runners on second trying to figure out the sign sequence and get the pitch and pass it on to the hitter, explained MLB Executive Theo Epstein. With electronic communication, teams no longer need to change signs or hold mound conferences when runners reach second base.
Widespread Adoption Across Baseball Levels
Professional baseball’s embrace of the technology has been swift. Despite early problems, all 30 MLB clubs started to use PitchCom in some way during the 2022 season. The system’s use is optional, not mandatory, but its practical advantages have driven near-universal adoption.
College baseball has followed suit with equal enthusiasm. The NCAA Playing Rules Oversight Panel approved allowing the use of one-way electronic communication devices for the purpose of calling pitches and plays, with the rule going into effect for the 2021-22 academic year. Usage statistics reveal rapid growth: over 3 million pitch calls were sent through GoRout Diamond wearable pitch calling devices in baseball in 2024, with 25 states having Division II baseball teams that use wearable pitch calling technology.
The technology’s reach extends beyond elite levels. Early feedback from 2024 games suggests a 15–20% increase in average pitch-calling time pace, allowing for a more dynamic and engaging experience on the field at high school and youth levels where the technology is being adopted.
Security & Competitive Integrity
Modern pitch calling devices address baseball’s most persistent concern: competitive integrity. All communications are encrypted, and teams may opt to replace pitch names such as “fastball” with code words. This encryption represents a fundamental shift from the vulnerability of visual signals to secure digital communication.
The security measures have effectively eliminated traditional sign-stealing concerns. Unlike the analog methods that made the Astros scandal possible, these digital systems operate on protected frequencies that cannot be intercepted with standard equipment. The technology has restored confidence in fair play at levels where competitive balance matters most.
The Human Element Remains
Despite technological advancement, baseball’s strategic depth hasn’t diminished—it’s evolved. Some teams have a habit of tinkering with and adding to their pitch calls. Though PitchCom comes with a standard collection of pre-set tracks, a number of clubs decided to record their own. Creative applications emerged: One reliever had his team program in the voice from the video game Mortal Kombat saying “Finish him,” while Guardians catcher Austin Hedges has become known for his “f— yeah” button.
The technology has also enabled new strategic possibilities. Starting with these rules changes, a player on the field or coaches in the third- or first-base boxes can initiate one-way communication devices to relay signals or instructions to offensive or defensive players in college baseball, expanding tactical options beyond traditional limitations.
Looking Forward
The evolution from the Astros scandal to widespread adoption of pitch calling technology represents more than technological progress—it illustrates baseball’s capacity for self-correction. What began as a crisis of integrity has transformed into an opportunity for innovation.
Companies continue developing increasingly sophisticated systems. GoRoute’s latest pitcher communication devices demonstrate how the technology continues advancing, with improvements in reliability, security, and user experience.
Since the scandal, MLB has increased security in replay rooms and introduced a transmitter-receiver device called PitchCom that allows the catcher and pitcher to communicate without hand signals. This transformation from vulnerability to security represents a fundamental shift in how baseball approaches technological integration.
The story of pitch calling devices is ultimately about baseball’s resilience. The same sport that was nearly derailed by technological cheating has emerged stronger, faster, and more secure through technological innovation. From the echoing bangs in Houston’s dugout to the encrypted whispers in today’s receivers, baseball has proven that technology, when properly implemented, enhances rather than diminishes the game’s essential character.
As the 2025 season approaches, with adoption rates climbing across all levels of play, pitch calling devices have become less about preventing the next scandal and more about perfecting the next pitch. In a sport defined by tradition, that evolution might be the most remarkable transformation of all.
