Mariners rack up another whiff on a KBO star amid Padres shopping spree

The Seattle Mariners didn’t just “miss out” on a player this week. They missed out on a type of move that’s supposed to be right in their wheelhouse: Cheap enough to stomach, flexible enough to fit, and intriguing enough to matter.

The infielder Sung-mun Song has reportedly signed with the San Diego Padres for a three year, $13 million contract, pending a physical, per FanSided's Robert Murray. While the Padres may be excited about Song's potential, no one is completely sold on him immediately becoming a "star" when he arrives in the U.S. However, with so many players receiving multi-million dollar contracts to provide depth, three years at $13 million for an infielder who recently showed pop with his bat is a steal.

Padres land Sung-mun Song and it’s exactly the kind of move Mariners needed

Song is not arriving as a "mystery box," with some highlights and a shrug. The infielder just concluded a large season with the Kiwoom Heroes, with a batting average of .315, an OBP of .387, a slugging percentage of .530, 26 HRs and 90 RBIs. If we place the normal "KBO to MLB translation" warning label on top of these numbers, it still doesn't appear to be empty stats. This is the same type of player that teams want to believe they can take and polish into something even better than what he was last season.

And then there’s the Padres, who are behaving like A.J. Preller is playing the offseason on a controller with the turbo button stuck. San Diego re-upped Michael King late in the night on Dec. 18, then followed it with the Song agreement before the rest of baseball had finished its morning coffee. It’s chaotic. It’s aggressive. And, annoyingly, it’s targeted: they’re stockpiling options without paying the “we’re desperate” tax.

From the Mariners’ angle, this one stings because the fit is so obvious. Second base and third base aren’t exactly etched in stone heading into 2026. Seattle has candidates, sure, but it’s not hard to imagine a spring where the best version of the lineup is the one that creates competition instead of hoping it appears. Song has mostly been a third baseman, and he’s logged time at second and first over his career — the kind of multi-spot versatility the Mariners usually love because it turns a roster crunch into a roster advantage.

Instead, it’s another “would’ve been perfect” depth swing landing in another division. And while Seattle doesn’t need to chase every shiny new toy, it’s fair to wonder how many times the Mariners can watch value plays go elsewhere before the margins stop being margins — and start becoming the whole story.