Major League Baseball is taking steps to curtail sign stealing in the digital age, according to multiple media reports.

Commissioner Rob Manfred has circulated a five-page memo to teams enforcing the league’s existing sign-stealing rules and outlining new ones governing the use of technology and replay systems.

Teams may not position cameras between the foul poles in the outfield if not for broadcast purposes. Team replay assistants, who help notify managers when to challenge a call on the field, will have access only to the live game broadcast and will be monitored by a security expert. All other TV monitors available to players and coaches, such as screens in the bullpen or clubhouse, will show the live game broadcast on an eight-second delay.

Teams found in violation of the rules could be punished with forfeited draft picks and international spending money.

Sports Illustrated first reported the changes.

Sign stealing is an age-old practice in baseball. Runners on second base commonly peer in at a catcher’s signs to tip off hitters as to what pitch is coming next. Manny Machado, as a member of the Los Angeles Dodgers, did it with great success against the Boston Red Sox during the 2018 World Series. Coaches and fielders study opponents to decipher whether a base runner is stealing or a batter is bunting.

But as technology has crept into baseball dugouts, teams have discovered less legitimate ways to decode signs.

The Red Sox in 2017 were caught using an Apple Watch in the dugout to steal signs from the New York Yankees. A member of Boston’s replay team would communicate with a trainer in the dugout, who would pass along information to players going up to bat.

Boston in turn accused the Yankees of running a similar racket using a television camera from the YES television network, which is partially owned by the Yankees.

Both the Cleveland Indians and Red Sox in the 2018 playoffs accused the Houston Astros of attempting to steal signs by recording their dugout. Houston had positioned a staffer in the third base photographers’ well with a camera. MLB cleared the team of wrongdoing but told playoff teams to quit videotaping one another. The rules being added for 2019 codify the restrictions Manfred put in place during the playoffs.

“There’s some unintended consequences that come with the advancement of technology,” Astros Manager A.J. Hinch told the Associated Press during the 2018 American League Championship Series. “It’s a leaguewide conversation that needs to happen in time. It’s happening right now during a really important series, and I just think it’s bigger than us. It’s bigger than any team. It’s bigger than any series. It needs to be corralled because of the state of the concern over it.

“The competitive edges nowadays are so narrow. You’re trying to find everything you can. And whether that’s pitch tipping, pitch sequencing, changing your signs, changing your location of your defenders — this is a bigger topic that’s going to take a lot more time than an overnight story and concern and people’s curiosities.”

Ballclubs in previous eras used all kinds of wily tricks to steal signs. The New York Giants in the 1950s positioned a powerful telescope in the outfield of the Polo Grounds and signaled down to the bullpen what pitch was coming next. A teammate in the bullpen would hold up a baseball for the batter to see, and if he threw the baseball up in the air, the batter knew an off-speed pitch was on the way. If not, a fastball was coming.

The system helped the Giants defeat the Brooklyn Dodgers for the National League pennant in 1951 on Bobby Thompson’s walk-off home run called “the shot heard round the world.”

(Thompson, who died in 2010, told the New York Times he didn’t use the system during the famous home run. “I was always proud of that swing,” he said.)

The use of binoculars (or a telescope) or electronic devices is illegal in today’s rules. Everything else is fair game, however.

For that reason, players and coaches often take up the burden of enforcing baseball’s “unwritten rules” that frown upon, among many infractions, those caught stealing signs. (The punishment is frequently getting drilled in the ribs by a pitcher.) The practice is meant to be done subtly so as not to show up an opponent and to avoid tipping off another team of the advantage gained.

“I’m always hesitant to use the word cheating, because that already implies that what you’re doing is wrong,” Shawn Klein, a sports ethicist and Arizona State University philosophy lecturer, said of sign stealing.

The practice isn’t necessarily wrong, he said, especially if every team has the same opportunity to do it. What likely concerns MLB leaders are the lengths teams have taken to protect their signals. Even without runners on base, catchers will use an entire series of signs to call a pitch. Managers and base coaches have dozens of dummy signs to fool defenses. Baseball has even developed the “wipe off” sign, where a coach can call for a specific play, then cancel it just to throw an opponent off the scent.

That takes a lot of time and slows down the pace of play, which hurts the game in the eyes of consumers, even if there’s a lot of action going on behind the scenes.

“If you’re an ethical fan, you want your team to play by the rules and play in a way that is sportsmanlike,” Klein said. “But you also want them to toe the line as well and know the rules and use the rules to their advantage. That’s part of the strategy of playing the game. Sometimes that’s going to cross the line. "

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