Haruya Tanaka (Chiba Lotte Marines):
The 20-year-old RHP in his second season in Nippon Professional Baseball is breaking out in 2025. After averaging under 92 MPH on his fastball in 2024, it has climbed over 2 MPH on average in 2025 to 94 MPH. He has topped out at 97 MPH. He has a 2.12 ERA and 21 strikeouts in 17 innings. After losing Rōki Sasaki in the offseason to the Dodgers, the Marines have developed another top-of-the-rotation arm for years to come.
Ryusei Terachi (Chiba Lotte Marines)
The 19-year-old catcher has been a semi-regular in the Marines’ lineup in 2025. After spending his winter playing in the Australian Baseball League, where he posted a .762 OPS, he has taken a big jump in his second season in NPB. He has an .852 OPS in 2025 with 2 HR, and on April 18th, he had his first career multi-HR game against Rakuten. He became just the 4th teenage catcher ever to have a multi-HR game in NPB history and the first teenager to do it in NPB since Munetaka Murakami in 2019.
Seiya Watanabe (Seibu Lions):
The rookie OF has started his career in NPB in a big way. He has a .933 OPS with two doubles and two triples. He is second in NPB with a .408 average on the season. He has yet to homer, but that is a matter of time. He’s also shown some really solid defense in LF. He had one of the hardest-hit balls in the recent NPB season last week when he had an exit velocity of 111.2 MPH. He became the first Seibu Lions rookie to have five consecutive multi-hit games this week in the previous 42 years. He is a future superstar in the making in NPB.
Shinya Sugai (Seibu Lions):
The 21-year-old lefty has bounced back from struggles in NPB in 2024 to be really solid to start 2025. He has posted a 2.18 ERA and 16 strikeouts in 20.2 innings. He was one of the better starters in the minors last season and has carried that success over to Seibu’s top team. While the fastball velocity won’t blow you away at 88-91, he has been able to generate swing and misses on the fastball. He has given Seibu another high-quality arm in the rotation that has helped lead Seibu to a surprising start in 2025.
Shunsuke Nakamori (Chiba Lotte Marines)
After a solid 2024 in NPB, Nakamori has taken a massive leap in 2025 out of the bullpen. He has seen his average fastball velocity jump 4 MPH to nearly 94 MPH. His strikeout rate has jumped 16%. While the ERA has jumped from 2.63 to 2.45, his FIP is a career-best 1.85. He is quickly establishing himself as one of the better relievers in all of NPB.
Hyun-bin Moon (Hanwha Eagles)
The 21-year-old third baseman is having his breakout season in the KBO. After homering 10 times combined in 240 games in the previous 2 seasons, Moon has already hit four this season. He also stole six bases in 31 games. He had 3 in 103 games in 2024. He has an OPS of .818 in 2025. That is a 66-point jump from 2024.
Seung-yeup Na (Lotte Giants):
The first baseman was one of the KBO’s breakout stars in 2025. After posting an .880 OPS and 7 HR in 2024, he has seen his power numbers take a big jump in 2025. He has posted a .944 OPS and 7 HR in 35 games this season. His strong 2025 has made him a prime candidate to take over as Korea’s starting first baseman in the 2026 World Baseball Classic.
Woo-joo Jeong (Hanwha Eagles)
The second overall pick in the 2025 KBO Draft has shown why he was taken in round 1. With a fastball that hits the mid-90s, the 18-year-old has been one of the most electric relievers in the KBO. In his last 12 innings pitched, he has a 3.00 ERA with 20 strikeouts and just four walks. Although just 18, he has an excellent shot at making Korea’s bullpen for the 2026 WBC. With a team lacking big-time velocity, the young flamethrower will be a standout arm for the Koreans.
Dong-ju Moon (Hanwha Eagles):
The 21-year-old RHP, widely expected to be the next Korean star starting pitcher, is having his best season as a full-time starter in the KBO in 2025. He has a 3.03 ERA with 32 strikeouts in 29 2/3 innings. He has struggled to generate a ton of strikeouts despite being one of the few KBO starters who can touch the mid to upper 90s on the fastball. That’s been a different story so far in 2025. He should be the Korean ace at the 2026 World Baseball Classic.
Braulio Cavero (Acereros de Monclova):
The 19-year-old CF is the youngest player getting at-bats in LMB, but is the best hitting prospect currently in the league. At the U18 Americas qualifier this past summer, he posted a 1.163 OPS and a HR for Mexico. In a tournament filled with future first-round picks from the US, Cavero had the best performance of any hitter. He’s 2 of 9 this season in limited action with two doubles. He had 4 HR in the spring for Monclova and should be given more opportunities as the season progresses. A strong showing could see him getting serious looks from MLB teams and potentially making that jump.
