KBO Star Song Sung-mun Agrees to 4-Year, $15M Deal with San Diego Padres, Source Says

Song Sung-mun, a late-blooming star infielder from the Korea Baseball Organization (KBO), is headed to Major League Baseball. The 29-year-old former Kiwoom Heroes player has agreed to a four-year, US$15 million contract with the San Diego Padres, a source privy to the situation said Monday.

The Associated Press also reported the financial details, though the deal is not yet official as the Padres have not made a formal announcement. Song was posted for all 30 MLB clubs in November, and his negotiating window was set to close Sunday. According to the source, however, the club's confirmation is a mere formality as Song has already signed the contract.

After a quiet start to his career which began in 2015, Song exploded over the past two seasons to become one of the KBO's elite players. He posted a .340/.409/.518 slash line with 19 homers and 21 steals in 2024, and followed it up with a .315/.387/.530 line, 26 home runs, and 25 steals in 2025. His performance earned him his first Gold Glove award at third base this year.

Primarily a third baseman, the left-handed hitting Song offers defensive versatility, having also played first and second base. This flexibility is a key asset for MLB rosters.

According to the AP, the contract includes a $1 million signing bonus. His salary will escalate from $2.5 million in 2026 to $3.5 million in 2028. The deal also contains a $4 million player option for 2029 and a $7 million mutual option for 2030, which includes a $1 million buyout.

Song is the sixth player from the Kiwoom Heroes to sign an MLB deal through the posting system, a testament to the club's scouting and development prowess. He follows in the footsteps of players like Kim Ha-seong (now with the Atlanta Braves), Lee Jung-hoo (San Francisco Giants), and Kim Hye-seong (Los Angeles Dodgers). With this move, Song becomes the third former Hero currently playing in the competitive NL West division.

Under the posting agreement, the Padres will pay the Heroes a release fee of $3 million, 20 percent of the contract's guaranteed value.

PRISM Insight: Song Sung-mun's signing reinforces the Kiwoom Heroes' reputation as a premier talent pipeline to MLB, rivaling even some Japanese NPB teams. This isn't just about individual stars; it's a testament to a sustainable development model where KBO-proven talent offers a high-upside, cost-effective alternative for MLB teams in a competitive free-agent market.