Michael Dwyer/Associated Press

En route to winning the World Series in 2018, the Boston Red Sox reportedly used their replay room to decode the opposition's signs.

According to Ken Rosenthal and Evan Drellich of The Athletic, three anonymous people who were part of the Red Sox organization in 2018 said some players went to the replay room during games to gain information regarding their opponents' signs.

"We were recently made aware of allegations suggesting the inappropriate use of our video replay room," the Red Sox said in a statement, via Rosenthal. "We take these allegations seriously and will fully cooperate with MLB as they investigate the matter."

Boston's alleged misuse of the replay room came after a crackdown from Major League Baseball. Ahead of the 2018 season, MLB made it clear that the replay rooms could be used only for determining whether to challenge plays and not to steal signs.

Both the Red Sox and New York Yankees were fined in 2017 for electronic sign stealing, but that reportedly did not deter the Red Sox from continuing to do so.

Boston went 108-54, won the American League East and then ran through the Yankees, Houston Astros and Los Angeles Dodgers during the playoffs. While the sign-stealing method may have been effective during the regular season, those close to the situation don't believe it contributed to Boston's playoff success.

Per Rosenthal and Drellich, Major League Baseball did not monitor replay rooms during the 2018 regular season, as teams operated on the honor system. That changed during the playoffs, as "in-person monitors" were added to the rooms.

Although sign stealing may not have been effective during the 2018 postseason, one member of the Boston organization during that season acknowledged the team was still breaking the rules before that: "It's cheating. Because if you're using a camera to zoom in on the crotch of the catcher, to break down the sign system, and then take that information and give it out to the runner, then he doesn't have to steal it."

While the Red Sox have declined to comment on the allegations, MLB released the following statement:

"The Commissioner made clear in a September 15, 2017 memorandum to clubs how seriously he would take any future violation of the regulations regarding use of electronic equipment or the inappropriate use of the video replay room. Given these allegations, MLB will commence an investigation into this matter."

Sign stealing has been a hot-button issue in recent years, and the Houston Astros have been the primary focus since the conclusion of the 2019 season.

In December, SNY's Andy Martino reported the Astros admitted to using a live feed from a center field camera to steal signs in 2017, which was the season that saw them win their first World Series championship.

According to Rosenthal and Drellich, Alex Cora helped devise the Astros' sign-stealing system while he was their bench coach and was then hired as Boston's manager in 2018.

The Athletic also reported that some within the sport believe the Astros' sign-stealing technique was more egregious than Boston's since people on the field were involved with stealing signs in Houston.

Neither the Astros nor the Red Sox have received a punishment from Major League Baseball yet, but both could be subject to fines or more.