Padres sign KBO reliever with strong strikeout rates

The Padres are in agreement with reliever Woo Suk Go on a two-year, $4.5M contract, reports Joel Sherman of the New York Post (on X). The deal includes a mutual option for the 2026 season, according to Dennis Lin of the Athletic (X link). San Diego will also owe a $900K posting fee to the LG Twins of the Korea Baseball Organization. The Post’s Jon Heyman had reported Tuesday night the sides were nearing a deal.

Go, a 25-year-old righty, has pitched parts of seven seasons in the KBO. He has worked as a pure reliever throughout that time, operating as the LG Twins closer for the past five years. After struggling during his first two seasons as a teenager, Go has been a solid bullpen arm for a half-decade.

He has rattled off four seasons with a sub-4.00 ERA, including three campaigns allowing fewer than 2.20 earned runs per nine. Go surpassed 30 saves in each of 2019, 2021 and 2022. He has fanned more than 26% of batters faced in each of the last five years, topping the 30% mark in the last two seasons.

While Go has consistently shown the ability to miss bats, he hasn’t always been around the strike zone. He has walked more than 10% of opposing hitters in four of his seven seasons. Go issued free passes to an alarming 11.6% of batters faced last year, contributing to a 3.68 ERA that made for more of a solid than exceptional platform showing.

Public scouting reports have generally pegged Go as a likely middle reliever at the big league level. Eric Longenhagen of FanGraphs writes that Go leans primarily on a mid-90s fastball and low-90s cutter while occasionally mixing in a curveball. That’s an intriguing arsenal, but the fringy control could make him a risk in higher-leverage spots.

The Twins made Go available via the posting system on Dec. 4. That opened a 30-day period for him to sign with a major league club. (Unlike Japan’s Nippon Professional Baseball, whose posting windows last 45 days, there’s a 30-day opening for South Korean players). That was concluding this afternoon. If Go hadn’t signed with an MLB team by 4:00 pm CST, he’d have remained with the Twins for another season.

San Diego has been one of the sport’s most aggressive teams in targeting players making the jump from Asian professional leagues. They recently signed lefty Yuki Matsui to a five-year, $28M pact as he came over from NPB. San Diego has added Ha-Seong Kim from the KBO and the likes of Nick Martinez and Robert Suarez from NPB in previous offseasons.

With Josh Hader, Martinez and Luis García hitting free agency, the Padres have Matsui and Suarez as their top two leverage relievers. Go joins that mix alongside righty Enyel De Los Santos, whom San Diego acquired from the Guardians in exchange for Scott Barlow this winter. Heyman suggested that Go could compete for the closer job.

Under the MLB-KBO posting agreement, the release fee is proportional to the size of the contract. For players guaranteed $25M or less, it is calculated as 20% of the contract value. The $900K fee brings San Diego’s total outlay for Go to $5.4M. In all likelihood, the pitcher will return to the open market after the 2025 season. While he’ll obviously be well shy of six years of MLB service, most major league deals for players from a foreign professional league include a clause that sends the player back to free agency once the contract expires.

The deal’s $2.25M average annual value brings San Diego’s projected luxury tax number to roughly $212M, according to Roster Resource. That’s $25M shy of next year’s lowest threshold. Distributing the salaries evenly would put their actual payroll in the $156M range. Even in an offseason defined by budgetary limitations, adding Go shouldn’t have much of an impact on San Diego’s ability to continue bolstering the roster. The Padres still need one or two outfield acquisitions and would benefit from a back-of-the-rotation starter.