Song Sung-mun, formerly of the Kiwoom Heroes, poses with the trophy after being named the Player of the Year at the Real Glove Award ceremony at the Grand Walkerhill Seoul, Dec. 1. Yonhap
Song Sung-mun, a late-blooming star who has been among the best players in Korean baseball the past two seasons, has signed with the San Diego Padres, a source privy to the situation said Monday.
The 29-year-old infielder, formerly of the Kiwoom Heroes in the Korea Baseball Organization (KBO), is taking his talent to Major League Baseball (MLB) on a four-year deal worth $15 million, according to the source.
The Associated Press also reported the financial details of Song’s contract, but the Padres had not officially confirmed the deal as of this writing.
Reports of Song’s deal with the Padres first surfaced Friday.
Song had been posted for all 30 MLB clubs in November, and his 30-day negotiating window was to close at 5 p.m. (U.S. Eastern time) on Sunday, or 7 a.m. Monday (Korean time).
While the Padres had not made their announcement by the posting deadline, the source said Song had already put pen to paper and the club’s confirmation was a mere formality.
Song made his KBO debut with the Heroes in 2015 after being selected in the fifth round the previous year, but he only had his first breakout season in 2024, when he batted .340/.409/.518 and set career highs with 19 homers, 104 RBIs and 21 steals.
Song Sung-moon speaks after winning the third baseman award at the 2025 Shinhan SOL Bank Golden Glove Awards ceremony in Seoul, Dec. 9. Yonhap
This year, Song posted a .315/.387/.530 line, along with 26 home runs, 90 RBIs and 25 steals. He also earned his first Golden Glove award at third base as the best overall player at his position and picked up his first KBO Fielding Award at the hot corner. He ranked second in the KBO with 6.84 wins above replacement.
Song, who bats left and throws right, is primarily a third baseman but has also spent time at second base and first base in the KBO. He also played shortstop in high school and has said he could play that position if asked in MLB.
Song is the sixth Heroes player to land a major league deal through the posting system, joining Kang Jung-ho (Pittsburgh Pirates), Park Byung-ho (Minnesota Twins), Kim Ha-seong (San Diego Padres), Lee Jung-hoo (San Francisco Giants) and Kim Hye-seong (Los Angeles Dodgers). Of this group, Kim Ha-seong is now with the Atlanta Braves, while Lee and Kim Hye-seong are still with the teams that signed them.
Song will be the third ex-Hero to join the National League West, alongside Lee and Kim Hye-seong.
According to the Associated Press, Song will receive $1 million as a signing bonus in two equal installments, in 30 days and then on Jan. 15, 2027. His salary will be $2.5 million in 2026, $3 million in 2027 and $3.5 million in 2028.
Song has a $4 million player option for 2029, and there is a $7 million mutual option for 2030 with a $1 million buyout.
The Padres will pay for an interpreter and round-trip airline tickets from Korea.
Based on the posting agreement between the two leagues, a KBO team that loses a player to an MLB club through the posting process receives a release fee.
If the player’s MLB contract has a total guaranteed portion of less than $25 million, then the release fee is 20 percent of the total guaranteed amount.
In Song’s case, the Padres must pay the Heroes $3 million and will also owe a supplemental release fee of 15 percent of triggered salary escalators.
If Song wins the Rookie of the Year award in 2026, his salary for 2027 will rise by $1 million. If he finishes among the top five in MVP voting, then his salary in all remaining years of his deal will go up by $1 million each.