Byun Sangil

Byun Sang-il (; born 14 January 1997) is a South Korean professional Go player.

Career Byun Sang-il was born in Jinju, South Gyeongsang Province. He studied Go with local 9-dan professional , before moving to Seoul in 2007 to further pursue Go. There, he first went to Lee Sedol's baduk dojang, and later Golden Bell Baduk Dojang. He earned professional 1 dan rank in January 2012, when he was 15 years old.

In 2018, he led his team Posco Chemtech to win the Korean Baduk League, and was named league MVP. His record was 10 wins and 4 losses in his regular league games and 2 postseason wins.

He won the Guksu Mountains International Baduk Championship in 2021, defeating Shin Jinseo in the final round. He also won the Crown Haitai Cup in 2022, a tournament for players under 25.

He won a major international championship in the Chunlan Cup in July 2023, with a 2–0 victory over Chinese player Li Xuanhao in the finals. Later that same month, he won Korea's GS Caltex Cup for the first time, after having been the runner-up the previous two years.

His highest ranking has been number two in the Korea Baduk Association's official rankings of Korean players, which he first reached in 2022. He is currently number three among Korean players.

2025 LG Cup controversy

Byun won his second major international tournament title in the 29th LG Cup World Baduk Championship in January 2025, becoming the first player in the history of Go world championships to claim the title without winning an actual on-board game, with the outcome decided entirely by referee rulings.

Byun was declared the winner of the best-of-three final in an unprecedented event after his opponent Ke Jie was disqualified in game 2 for rule violations and forfeited in game 3 due to a dispute over the timing of the penalty for another similar rule violation. A significant controversy in the tournament was around the enforcement of the rule violated by Ke Jie, which was introduced by the Korea Baduk Association in November 2024, well after the LG Cup had already commenced in May. The change in rules midway through the tournament sparked debate, with critics arguing that it violates sports conventions and renders the final's penalties questionable.

During the second game of the LG Cup final, Ke Jie violated the rules twice. The first violation resulted in a two-point penalty and a warning. Later in the game, Ke Jie again failed to place a captured stone on the bowl lid, prompting an objection from Byun Sang-il. As per the rules, Ke Jie was penalized for the second violation with an immediate loss. This marked the first instance in the history of the Go World Championship final where a game was terminated due to a player's rule violation.

In the third game the next day, Ke Jie failed to immediately place two captured stones on the bowl lid after capturing them. Ke Jie and the Chinese side objected to the referee's handling of the situation, because the referee paused the game after several moves had already been played, at a time during Byun's turn, which gave him additional thinking time. Ke Jie said that the referees had repeatedly paused the games during Byun's turns over the games in the final. Ke Jie informed the referee that he did not oppose the penalty but requested that the game be resumed immediately and paused only after Byun had made his move. However, the referee dismissed the request, which, from Ke Jie's perspective, made it seem as if the referee was extending the pause time to give Byun additional time and his actions have already affected the outcome of the game. (According to the Chinese Go rules about suspending games and sealing moves as well as the Adjournment rule of GO, the player who has made their move should immediately leave the playing area. The player whose turn it is must think and record the point where they plan to play on a designated piece of paper, which is then sealed and handed to the referee. When the game resumes, the referee opens the sealed paper and makes the move at the marked location, and the game proceeds. The new Korean Go rules do not provide detailed regulations on this matter. The Chinese Weiqi Association released a statement saying that they do not accept the outcome of the third game.

During the LG Cup award ceremony, Byun stated: "The game ended in an unpleasant manner, which made me feel very uncomfortable. I completely understand Ke Jie's position." He also told reporters that he was unaware of the rule before the referee announced Ke Jie's violation for failing to properly handle captured stones. Byun further expressed his belief that the rule is unnecessary, as it does not affect the outcome of the game.

International competitions (W) Winner; (RU) Runner-up; (SF) Semifinalist; (QF) Quarterfinalist; (R16) Round of 16; (R24) Round of 24; (R32) Round of 32; (R64) Round of 64.

Note 1: Some competitions last for more than one year. Usually the beginning year of the competition is recorded as the year of competition. Note 2: The light green background indicates that the player is still competing in the competition. Note 3: '×' means the player did not participate (or lost in the qualification round), while '-' means the competition was not held in that year. Note 4: The result of Nongshim Cup means the result of the player (matches won : matches lost). The result '0:0' means the player qualified for his/her national team of Nongshim Cup, and the team won before the player compete in the cup.