Report: Posting window for Hyeseong Kim to begin Wednesday

Infielder Hyeseong Kim is expected to be officially posted by the Kiwoom Heroes of the Korea Baseball Organization on Wednesday, per Jon Morosi of MLB Network. Once it’s official, that will start a 30-day window where all MLB clubs can negotiate with Kim and his representatives. If no deal is signed in that time, he will return to the Heroes for the 2025 season.

Kim, 26 in January, will be considered a “professional” under MLB rules because he is at least 25 years old and has at least six years of experience in a foreign league. As such, he can sign a deal of any length or dollar amount. That’s in contrast to someone like Roki Sasaki, who is only 23 years old and will therefore be capped by the international bonus system.

It isn’t likely that Kim will secure a massive deal, but he could still have some interest. He is expected to provide a somewhat similar skillset to his former double play partner Ha-Seong Kim, no relation, as both players are considered sure-handed defenders at multiple spots on the diamond. Hyeseong has mostly played the two middle infield spots, but also with brief stints at third base and in the outfield corners.

Offensively, Hyeseong is a tick below Ha-Seong, however. Hyeseong has slashed .304/.364/.403 in his eight KBO seasons whereas Ha-Seong hit .294/.373/.493 in his seven campaigns in Korea. The batting average and on-base numbers are fairly close but Ha-Seong clearly has the edge in terms of slugging. Hyeseong got to 11 home runs in 2024, a career high for him, whereas Ha-Seong had 19 or more homers in his final six KBO seasons, including 30 in the final year.

Still, Hyeseong's youth and athleticism should work in his favor. As mentioned, he is considered a strong defender and could be placed at multiple different positions. He has stolen between 20 and 46 bases in each of the past six seasons.

MLBTR predicted he could secure a three-year deal with a $24M guarantee as part of the annual Top 50 Free Agents post. However, predicting the interest in a player making the move from overseas can be difficult, as players like Jung Hoo Lee and Masataka Yoshida both proved to have much more earning power than was assumed by forecasters.

The Mariners are reportedly interested in Kim, but it stands to reason that plenty of others would be in the mix as well, given his versatility. Clubs like the Giants, White Sox, Marlins, Brewers and others are speculative fits. Players like Willy Adames, Ha-Seong Kim, Gleyber Torres and others are also available in the middle infield free agent market. They will be joined by Hyeseong, but the 30-day posting window means there will be clarity on his status by the first few days of 2025 at the latest.

In addition to the money going to Kim, a signing club will also have to pay a posting fee to the Heroes, the value of which will depend upon the size of the contract. The fee will be calculated as 20 percent of the contract’s first $25M, plus 17.5 percent of the next $25M and 15 percent of any dollars thereafter. Additional earnings, such as performance bonuses/incentives or salaries on option years fall under that purview once they are unlocked or exercised.