The 2012 South Korean professional baseball match-fixing scandal was the first match-fixing scandal in the history of the KBO League. The scandal came to light in 2012 after a broker implicated in the 2011 K League match-fixing scandal and the V-League match-fixing scandal revealed that match-fixing had also occurred in professional baseball. As allegations spread, several players came under suspicion, and pitchers Moon Sung-hyun, , and Kim Sung-hyun were summoned by prosecutors for questioning. Among them, Park Hyun-joon and Kim Sung-hyun were found guilty of match-fixing-related offenses and were subsequently indicted. The KBO permanently expelled both players from professional baseball.

Background

Allegations

Following the exposure of the 2011 K League match-fixing scandal, concerns emerged that match-fixing—the practice of manipulating the course or outcome of a sporting event in exchange for money—had become widespread within South Korean professional sports. In February 2012, a separate match-fixing scandal was uncovered in the V-League, South Korea's professional volleyball league, further fueling suspicions that similar activities may have occurred in professional baseball and basketball. Although the structure of legal sports betting made match-fixing in baseball difficult, illegal betting websites offered wagering options that created opportunities for manipulation. Due to the nature of baseball, where altering the final result of a game is often more difficult than in other sports, illegal betting markets frequently accepted wagers on specific in-game events, such as whether a starting pitcher would issue a walk in the first inning. This enabled brokers to influence games by approaching individual pitchers rather than entire teams. Reports suggested that even ace pitchers from teams based in the Seoul metropolitan area were implicated.

On 13 February 2012, a broker who had previously been arrested for involvement in the K League match-fixing scandal disclosed during an investigation into the V-League scandal that match-fixing had also occurred in professional baseball and basketball, confirming long-standing suspicions within the baseball community. According to the broker, illegal betting operators exploited wagering categories such as "predicting the first walk of the game," which were not directly tied to the outcome of a match, making it easier to recruit starting pitchers and manipulate specific events during games.

Match-fixing in baseball was typically carried out through starting pitchers, whose participation and playing time were relatively predictable. Because the manipulated actions were often only loosely connected to the final result of the game, they attracted less attention than conventional forms of match-fixing. The broker reportedly disclosed the names of both the players and clubs involved, although those details were not publicly released by the media.

The broker alleged to have orchestrated the match-fixing scheme stated that two ace starting pitchers from Seoul-based KBO League clubs—either the Nexen Heroes, Doosan Bears, or LG Twins—had been involved. According to his testimony, the pitchers had been recruited during the 2011 season to intentionally issue walks in the first inning or throw a ball on the first pitch of a game. The broker reportedly worked alongside another broker and a former university baseball player from Daegu who had failed to reach the professional ranks. One of the recruited pitchers had reportedly attended the same high school as the former player, which facilitated contact between the parties. On 15 February, media reports cited prosecutorial testimony identifying the players as members of the LG Twins. As allegations spread throughout the KBO League, clubs conducting spring training overseas launched internal investigations. The Nexen Heroes, who were training in the United States, announced that pitcher Moon Sung-hyun had been approached by a broker involved in illegal betting operations but had rejected the proposal, providing the first public confirmation that an organized match-fixing network had attempted to recruit KBO League players. Meanwhile, a former KBO League All-Star claimed that organized crime groups had become involved in match-fixing and that both players and coaches were targeted for recruitment. The allegation was later determined to be false. Following reports linking the LG Twins to the scandal, general manager Baek Soon-gil traveled to Okinawa, Japan, where the club was holding its spring training camp, to investigate the allegations. Prior to his departure, Baek questioned players about possible involvement and contacted prosecutors regarding the reports, later stating that the allegations lacked factual basis.LG, "승부조작 선발 투수 2명?… 사실무근이다", 《일간스포츠》, 2012년 2월 15일 The atmosphere at the LG Twins' training camp reportedly became subdued after extensive media coverage of the scandal began on 15 February. The club repeatedly stated that interviews with players had uncovered no evidence of match-fixing and pledged full cooperation with prosecutors. The Doosan Bears also announced that their internal investigation had found no evidence of match-fixing. The Lotte Giants and Hanwha Eagles similarly stated that their own reviews had not identified any players involved in the scandal.

Managers of KBO League clubs participating in spring training expressed skepticism regarding the allegations, noting that intentionally issuing a walk is difficult even for professional pitchers and that they had never suspected their players of deliberately doing so. Nevertheless, they agreed that any proven instances of match-fixing should be dealt with severely. The KBO sought to dispel unfounded rumors by requesting a police investigation into an individual who had falsely claimed to be a former professional baseball player while providing fabricated information to media outlets. The individual had alleged that organized crime groups were involved and that players manipulated games through intentional errors, but suspicions arose when he spoke in a regional dialect inconsistent with the background of the retired player he claimed to be. The allegations were subsequently proven false.KBO, 야구 선수 사칭 허위제보자 수사 의뢰, 《동아일보》, 2012년 2월 15일 작성. KIA Tigers pitcher Yoon Suk-min indirectly denied any involvement in match-fixing through a message posted on Twitter, attempting to reassure fans amid growing speculation. The Daegu District Prosecutors' Office, which was investigating the V-League match-fixing scandal, stated that most media reports regarding baseball were based on rumors rather than verified testimony and that it had no plans to expand its investigation without concrete evidence. The KBO welcomed the prosecutors' position while emphasizing that preventive measures would continue and that severe penalties would be imposed if match-fixing were confirmed. The Korea Professional Baseball Players Association likewise criticized speculative reporting but called for a thorough investigation to determine the truth behind the allegations.

Although the names of the suspected players had not been officially disclosed, South Korean internet users widely speculated that the LG Twins players involved were and Kim Sung-hyun. Their names, along with that of Moon Sung-hyun, who was reported to have rejected a match-fixing proposal, became among the most searched terms on major internet portals. Subsequently, media outlets began reporting Park Hyun-joon's name and suggesting that he would be summoned for questioning by prosecutors. Reports indicated that investigators had secured testimony alleging his involvement in intentionally issuing first-inning walks. Park, who had served as the LG Twins' ace pitcher during the 2011 season, ranked fifth in the league in first-inning walks. However, while participating in spring training in Okinawa, he denied all allegations. Some observers also argued that his inconsistent control made it difficult to determine whether any walks had been intentional. Park further stated that he had never been contacted by brokers, while the LG Twins maintained that interviews with him provided no evidence of wrongdoing. Afterward, Park avoided contact with the media and declined to comment further on the allegations. Kim Sung-hyun, another player under suspicion, also denied involvement during interviews with both club officials and the media, explaining that he had historically performed poorly in first innings.

As speculation continued, opinions within the baseball community remained divided. While some considered the allegations implausible, others argued that any proven match-fixing should be punished severely. Many also urged the media to refrain from speculative reporting. Active KBO umpires stated that they had never noticed signs of match-fixing and expressed surprise at the allegations. One umpire remarked that there had not even been rumors within the sport, though he agreed that any confirmed misconduct should be punished harshly. The Ilguhoe, an organization composed primarily of retired KBO League players, criticized the media's speculative coverage and expressed concern that reports were focusing on game manipulation that did not necessarily affect final outcomes. Nevertheless, it urged prosecutors to continue investigating and eradicate the practice. Some observers, however, argued that launching investigations solely on the basis of rumors was inappropriate. The Daegu District Prosecutors' Office, which was responsible for investigating match-fixing in South Korean professional sports, reiterated that it would not establish a dedicated baseball investigation team and dismissed reports that Park Hyun-joon would be summoned, stating that players could not be questioned solely on the basis of rumors.

Investigation begins

On 16 February 2012, as several cases of match-fixing in professional volleyball were confirmed, suspicions surrounding the KBO League intensified. Prosecutors at the Daegu District Prosecutors' Office also secured testimony from a broker who claimed to have paid and Kim Sung-hyun several million won in exchange for intentionally issuing first-inning walks. Based on this testimony, prosecutors launched a formal investigation into the allegations. Initially, only Park and Kim were targeted for investigation and were expected to be summoned for questioning. However, as additional reports emerged regarding attempts to recruit players for match-fixing schemes, the possibility grew that the investigation would expand to encompass the entire KBO League. It was also reported that Moon Sung-hyun, who had stated that he had received a match-fixing proposal, would be summoned as a witness.