Moon Dong-ju's Fastball Drops 8 km in Korean Series Debut

Playoff MVP Struggles as Starter, Bullpen Falters in 8-2 Loss

[OSEN=Jamsil, Reporter Lee Sang-hak] Over the course of 8 days, Moon Dong-ju's maximum fastball velocity dropped from 162 km to 154 km. Moon Dong-ju (22), who won the Playoff MVP, struggled with his stamina and suffered a defeat in his Korean Series debut.

Moon Dong-ju started in the first game of the 2025 Shinhan SOL Bank KBO League postseason Korean Series (KS·best-of-seven) against the LG Twins at Seoul Jamsil Baseball Stadium on the 26th, pitching 4⅓ innings with 4 hits, 1 home run, 3 walks, 3 strikeouts, 4 runs allowed, 3 earned runs, and took the loss. After Moon Dong-ju, whom the team had relied on, failed to complete the fifth inning, the Hanwha bullpen faltered, and the offense managed only 2 runs, leading to an 8-2 complete defeat against LG.

Moon Dong-ju was Hanwha's standout performer in the playoffs. After undergoing bullpen testing in preparation for the postseason late in the season, Moon Dong-ju recorded a hold in the first game of the Samsung series (2 innings, 1 hit, no walks, 4 strikeouts, no runs) and a relief win in the third game (4 innings, 2 hits, 1 walk, 6 strikeouts, no runs), earning him the MVP.

In particular, in the first game, his personal best fastball speed of 161.6 km, rounded to 162 km, was displayed on the scoreboard, drawing gasps from fans. On that day, Moon Dong-ju threw 13 fastballs out of 29 total pitches, with an average speed of 157 km, showcasing his power.

After resting for two days, Moon Dong-ju pitched 4 innings and 58 pitches in the third game, increasing both his innings and pitch count. His fastball reached a top speed of 157 km and averaged 153 km, remaining formidable, but his velocity slightly decreased compared to the first game, where he compressed his effort into 2 innings. After the third game, Moon Dong-ju said, "My body felt really light in the first game, but today it felt a bit heavy. In a game like today, I thought focusing on speed would be difficult, so I tried to concentrate on my breaking balls and other pitches, and it worked out."

Hanwha, which suffered a painful comeback loss in the fourth game, extended the playoffs to a fifth game but did not use the "bullpen Moon Dong-ju" card again. Although there was a possibility of him being available for the bullpen after resting for two days, Manager Kim Kyung-moon said, "Baseball doesn't end this year. He threw over 50 pitches that day," and decided to save Moon Dong-ju for the decisive fifth game without overworking him.

Hanwha, which advanced to the Korean Series with their "one-two punch" Cody Ponce and Ryan Wysocki, selected Moon Dong-ju as the starter for the first game. Although Ryu Hyun-jin was also available after resting for 4 days, the team opted to deploy Moon Dong-ju first, who had demonstrated strong pitching in the playoffs. There was also a calculation that LG batters would struggle to time Moon Dong-ju's fast pitches due to a three-week gap since his last appearance, but this expectation was shattered from the first inning.

The first-pitch fastball Moon Dong-ju threw to LG's leadoff hitter Hong Chang-ki in the first inning was clocked at 148 km, not particularly fast by his standards. LG batters cut Moon Dong-ju's fastballs into foul territory. His breaking ball control also faltered. Against Kim Hyun-soo with one out and runners on first and second, two consecutive forkballs (the second and third pitches) sailed high, difficult for catcher Choi Jae-hoon to handle. This led to a passed ball, advancing the runners to second and third with one out, and Kim Hyun-soo's groundout to second allowed the runner from third to score, giving up the opening run.

With two outs and a runner on third, Moon Dong-ju allowed Moon Bo-kyung to hit a one-out, one-run double down the left-center gap. Although the 154 km fastball was high in the center of the zone, Moon Bo-kyung's bat did not lag, producing a quick and sharp line drive. The 154 km pitch was Moon Dong-ju's fastest of the day.

After giving up 2 runs in the first inning, Moon Dong-ju stabilized his breaking ball control from the second inning. He prevented additional runs until the fourth inning, but his pitches lacked dominance. In the fifth inning, a curveball to Park Hae-min became a solo home run, and Shin Min-jae capitalized on a high 150 km fastball on the first pitch down the middle, hitting a triple to right-center. Moon Dong-ju induced a groundout to third against Austin Dean but was pulled after No Si-hwan's throw home sailed wide, allowing the fourth run.

Moon Dong-ju threw a total of 81 pitches: 45 fastballs (top speed 154 km), 18 forkballs, 14 curveballs, and 4 sliders. Eight days prior, as a reliever, he reached a top speed of 162 km, but his velocity dropped by 8 km, showing signs of fatigue. After the game, Manager Kim Kyung-moon said of Moon Dong-ju, "It seemed more like his body wasn't fully warmed up early on rather than exhaustion." The colder weather also had an impact, and his control was poor in the early innings.

Moon Dong-ju was Hanwha's most potent weapon on the mound this autumn. He served as a high-leverage reliever, overpowering batters with his strong stuff and relieving the team's bullpen struggles. However, in the Korean Series, his role shifted to starter, causing the bullpen to unravel again. Moon Dong-ju himself lacked the same velocity and dominance as when he pitched out of the bullpen, leaving the impression that Hanwha's greatest weapon had vanished.