The Mariners have a solid bullpen, which includes proven commodities in Andres Munoz, Justin Topa, and Matt Brash anchoring the late innings. There were some growing pains with the group shortly after the Paul Sewald trade, as Munoz blew a series of critical games in August. The Mariners could look into the free-agent market to further solidify the roster's known strength by bidding on Korean Baseball League All-Star closer Go Woo-suk.
The posting window is 30 days long, which gives the Mariners time to flush out the rest of their offseason plan (Snell, Yamamoto, or trading pitching for a bat) and lay the groundwork for some transactions at the upcoming Winter Meetings.
The 25-year-old Go has a track record of sustained success since his KBO debut five years ago. He punches out opposing hitters at a solid 31% rate, but the walks are a little higher than the Mariners seem comfortable with (11.6% in 2023). However, the Mariners' pitching development lab has always leaned into unique traits even when the players have some known warts, a la Matt Brash, and his control issues. So, what does the high-leverage reliever offer?
The fastball ranges from 94 to 98 mph with some heavy sink that helps him induce groundballs (60%), which should intrigue the Mariners due to their emphasis on defense. Looking at the video, I see a ton of Justin Topa in Go. I'm sure Scott Servais wouldn't mind another established arm in the pen that fits the team's timeline and could add to a core in the same age range. Additionally, we've been banging the Jung Hoo Lee drum for the past few months, and adding his brother-in-law could turn this into a possible package deal.
According to the Yonhap News Agency, Go's availability will hinge on what kind of deal he can land because the more significant the contract, the more money via the posting fee goes to his current team, the LG Twins.