Prospect Retrospective: Jae Weong Seo

After managing the Norfolk Tides, the Mets’ Triple-A affiliate in 1995, manager Bobby Valentine left to manage the Chiba Lotte Marines, a team in Nippon Professional Baseball’s Pacific League. With a 55-73 record in 1994, the Marines ended the season in second-to-last place, in front of only the Nippon Ham Fighters. Manager Soroku Yagisawa was fired mid-season and replaced for the 1995 season by Valentine. The second gaijin to manage an NPB team, Bobby V led the team to a 69-58 record, second only behind the Orix Blue Wave. Though he had a two-year contact, he was fired after just one season. According to Marines general manager Tatsuro Hirooka, Valentine was let go “because he didn’t understand Japanese baseball,” though the Marines’ record and the adulation the fans showed Valentine said otherwise.

Valentine returned to the U.S. and became the skipper of the Tides once again. With 31 games left in the season, the Mets fired Dallas Green and promoted Bobby Valentine, who won 12 of the 31 games the Mets had left that season. In a position of influence and enjoying a good relationship with newly hired Mets GM Steve Phillips, Valentine recommended that the Mets intensify their scouting in an area that had traditionally been ignored by Major League Baseball: Asia. One of such players that were signed during this focus was Jae Weong Seo.

Born on May 24, 1977 in Gwangju, South Korea, Seo attended Gwangju Jeil High School and after graduating, attended Inha University, a private university in in Incheon where he was studying law. He dropped out in 1998 after the Mets approached and signed him to a contract with a $1.1 million signing bonus. “I could make a lot of money if I stayed in Korea,” Seo said of his studies. “The main reason I will stay in the United States is to be a major leaguer. And until I get my dream, I don’t want to go back.”

In addition to signing Jae Seo, the Mets also signed his older brother, 22-year-old outfielder Jae Hwan Seo, but most considered him a negligible addition to the organization, signed simply to aid his younger brother in assimilating to a new country and culture. According to Bobby Valentine, ‘’If he stays healthy and progresses as he should,’’ Valentine said, ‘’he will be an impact player at the major league level. He has those kind of abilities.’” With a fastball that hovered sat in the low-to-mid-90s, topping out at 95 MPH, a good changeup and a good slider, Seo certainly had all the tools to succeed in the majors.

His career in the United States unfortunately did not get off to a good start. He battled through elbow issues that limited his time on the mound for much of 1998. When he was able to pitch, he was excellent. Pitching 5.0 innings for the GCL Mets and 35.0 innings with the St. Lucie Mets, Seo combined to post a 2.03 ERA in 40.0 innings, allowing 30 hits, walking 10, and striking out 42. That winter, he joined the South Korean National team in the Asian Games, where he won a gold medal and secured a waiver for his compulsory military service. He returned to St. Lucie for the 1999 season and made just three starts before being shut down because of elbow pain. The elbow pain turned out to be a frayed ulnar collateral ligament, requiring Tommy John surgery to fix.

Seo did not pitch at all in 2000, returning to the mound in 2001. Taking the mound for St. Lucie for the first time in a year and a half, Seo posted a 3.55 ERA in 25.1 innings, prompting the Mets to promote him to Binghamton. The right-hander was even more successful there, posting a 1.94 ERA in 60.1 innings. Because he was on the older side when he first signed with the organization, and missed time because of his Tommy John surgery, the Mets pushed Seo, promoting him to the Norfolk Tides at the end of the year. The 24-year-old did not skip a beat, posting a 3.42 ERA in 47.1 innings. All in all, he posted a 2.77 ERA in 133.0 innings in his first year back, allowing 118 hits, walking 23, and striking out 91. As evidenced by his strikeout numbers, Seo’s stuff was not the same after the surgery. His fastball, which previously sat in the low-to-mid-90s and topped out around 95 MPH now sat in the high-80s, topping out at 90, 91 MPH.

The right-hander spent the majority of the 2002 season in Norfolk. In late July, he was called up to the majors, and on July 21, he made his major league debut, pitching a scoreless inning of relief against the Cincinnati Reds. He was sent back down to the minors and spent the rest of the season there, posting a 3.99 ERA in 128.2 innings with the Tides, allowing 145 hits, walking 22, and striking out 87.

Coming into spring training in 2003, Seo had become something of a forgotten man due to the time that he missed from Tommy John and the lack of explosive stuff that he possessed when he returned from it- manager Art Howe claimed that he had never even heard of Seo, highlighting the lack of faith the organization had in his future. But, as Robert Burns once said, “The best-laid plans of mice and men often go awry.” That spring, Pedro Astacio began experiencing shoulder problems and David Cone was experiencing pain in his hip, meaning that Seo unexpectedly found himself competing for a role in the pitching rotation. In the end, it came between him and southpaw Mike Bacsik, and Seo won. The 26-year-old ended up being one of the Mets’ most consistent pitchers that year, posting a 3.82 ERA in 188.1 innings, his workload and ERA second to only Steve Traschel on the team that year.

He was not as successful in 2004, posting a 4.90 ERA in 117.2 innings, allowing 133 hits, walking 50, and striking out 54. He spent about a month in Norfolk, from the end of July to the end of August, in an effort to right himself, but when he returned to the Mets in September, he did not pitch much differently. Some blamed newly hired pitching coach Rick Peterson, who challenged Seo to alter his mechanics and incorporate new pitches into his repertoire. No matter who was at fault, Seo’s struggles came at the worst possible time for his future career prospects.

In December 2005, Pedro Martinez signed a 4-year, $53 million contract with Mets. He would join veterans Steve Traschel and Tom Glavine, and Kris Benson and Victor Zambrano, both of whom were acquired via trades in 2004, leaving Seo as the odd man out for much of the year. He spent the majority of the season with the Tides, but when he was able to pitch at the major league level at the beginning and end of the year, he made the most of his time. All in all, he posted a 4.29 ERA in 121.2 innings with the Tides, and a 2.59 ERA in 90.1 innings with the Mets.

Prior to the season, he expressed his desire to be traded if he could not start, but the Mets did not do so until the season ended. On January 4, 2006, Seo was dealt to the Los Angeles Dodgers along with Tim Hamulack in exchange for relievers Duaner Sánchez and Steve Schmoll. He did not pitch particularly well for the Dodgers, posting a 5.78 ERA in 67.0 innings, and was traded in late June along with catcher Dioner Navarro and outfielder Justin Ruggiano to the Tampa Bay Devil Rays in exchange for pitcher Mark Hendrickson and catcher Toby Hall. His time with Tampa Bay wasn’t much of an improvement, and he posted a 5.00 ERA in 90.0 innings with them. He looked strong in spring training, but ended up posting an 8.13 ERA in 52.2 innings with them, getting demoted to the Triple-A Durham Bulls for the rest of the season.

After the 2007 season ended, Seo signed with the KIA Tigers of the KBO. Based on Gwangju, the Tigers had been his hometown team growing up. He would spend the next eight seasons with them, posting a cumulative 4.30 ERA in 745.1 innings, allowing 825 hits, walking 222, and striking out 417. After the 2015 season ended, Seo finally announced his retirement from the game of baseball. After retiring, the Tigers hired him as a coach, and he currently serves as the team’s pitching coach.

After signing with the Mets, Seo was considered among the top pitching prospects in the Mets’ minor league system. Tommy John surgery hurt his stock, but when he returned to the mound, he once again was considered a highly touted prospect. The velocity that he lost on his fastball, he was able to work around thanks to excellent control, but in the majors, he walked on a tight rope. When his command was on, he could work around a lack of an explosive fastball with his exceptional changeup and solid slider. When he was unable to locate his pitchers, hitters were able to simply wait on hittable pitches in the zone.