1. Early Life and Amateur Career
Daiki Tajima's journey in baseball began in his childhood, leading him through a successful amateur career before he turned professional.
1.1. Youth and High School
Tajima began playing soft baseball in elementary school, influenced by his father, joining the Takaraogi Fighters. In his sixth year, he served as the team's ace pitcher, leading them to a prefectural tournament championship. In junior high school, he transitioned to hardball, playing for the Kanuma Boys, and participated in the World Tournament during his third year.
He attended Sano Nihon University High School, where he earned a spot on the varsity bench by his first summer. In his first autumn, despite wearing jersey number 11, he became the team's main pitcher, contributing to consecutive advancements to the Kanto Tournament in both autumn and spring. By his second autumn, he wore the coveted jersey number 1 and led his team to the Best 4 of the Kanto Tournament, defeating strong teams like Yokohama High School, which featured future professionals Daiki Asama and Yujin Takahama, thereby securing a spot in the Spring Senbatsu Tournament. In the 86th National High School Baseball Invitational Tournament during his third year, he delivered a shutout victory in the first round against Chinzei. He followed this with a 10-inning complete game against Kazuma Okamoto's Chiben Gakuen and an 11-inning complete game against Junichiro Kishimoto's Meitoku Gijuku, marking three consecutive complete-game victories. Although his team was defeated in the semi-finals by Ryukoku University Heian (led by Keiji Takahashi), who eventually won the tournament, Tajima pitched an impressive 560 balls across four games, significantly contributing to his team's unexpected deep run to the Best 4. Despite being considered a strong candidate for the 2014 NPB draft, Tajima chose to pursue corporate baseball. This decision was driven by a series of injuries in high school, which led him to realize his physical limitations, as well as a desire to develop a sense of social responsibility and etiquette within a corporate environment before entering professional sports.
1.2. Corporate Baseball Career
After graduating from high school, Tajima joined JR East's corporate baseball team. In his second year (2016), he represented Japan in the 2016 WBSC U-23 World Cup, where Japan secured the gold medal. In his third year (2017), he participated in the 28th Asian Baseball Championship. In the final game, he pitched five scoreless innings, contributing to Japan's victory and earning the Most Valuable Player award for the tournament. He also showcased his dominance in the 88th Urban Baseball Tournament, where he achieved two consecutive shutout victories, helping his team reach the Best 8. His impressive performance earned him a spot on the Corporate Baseball Best Nine on December 7.
2. Professional Career
Daiki Tajima's professional career began with the Orix Buffaloes, where he has consistently been a vital part of their pitching rotation, navigating through injuries and contributing to multiple team championships.
2.1. Draft and Joining the Orix Buffaloes
On October 26, 2017, during the 2017 NPB Draft, Daiki Tajima was a highly sought-after prospect, receiving first-round nominations from both the Orix Buffaloes and the Saitama Seibu Lions. Through a lottery, the Orix Buffaloes secured the negotiation rights. On November 16, he officially signed a provisional contract with the Buffaloes, which included a signing bonus of 100.00 M JPY, an estimated annual salary of 15.00 M JPY, and an additional 50.00 M JPY in incentives. He was assigned the uniform number 29. His signing marked a significant moment for the Orix Buffaloes, as he was the first player to join the team after being a contested first-round pick since Tomoya Kawaguchi in 1997.
2.2. Orix Buffaloes Era
Daiki Tajima's professional career with the Orix Buffaloes has been a journey marked by promising debuts, battles with injuries, and significant contributions to the team's success.
2.2.1. 2018 Season
Tajima began his professional career by starting in the top team's spring training camp. He performed well during the open season, notably pitching six innings and allowing two runs to earn a win against the Hanshin Tigers on March 24, ultimately securing a spot in the Opening Day rotation. His professional debut came in the second game of the season against the Fukuoka SoftBank Hawks on March 31. Despite giving up a leadoff solo home run to Keizo Kawashima in the first inning and struggling with his control, he allowed only that one hit over five innings, earning his first professional win. However, his next start on April 7 against the Saitama Seibu Lions saw him struggle, giving up two runs in the fourth inning and being pulled after a bases-clearing triple, resulting in his first professional loss (3.1 innings, 6 earned runs). Throughout the early season, he was prone to giving up extra-base hits. On June 10, he had his worst outing, allowing eight runs in 3.1 innings against the Tokyo Yakult Swallows. Although he had been a fixture in the starting rotation since Opening Day, he was removed from the active roster on June 27 due to stiffness in his left elbow, and he did not return to the first team for the remainder of the season. In his rookie year, Tajima made 12 starts, finishing with a record of 6 wins and 3 losses and an ERA of 4.06. In the offseason, his salary was increased by 5.00 M JPY to an estimated 20.00 M JPY.
2.2.2. 2019 Season
Tajima made his return to the first team on June 5, 2019, against the Yokohama DeNA BayStars, earning his first win in almost a year with a strong performance of 5.2 scoreless innings on four hits. He started the first half of the season well, recording 2 wins and 0 losses in four starts. However, the second half began with three consecutive losses. Although he pitched six scoreless innings against the Hokkaido Nippon-Ham Fighters on August 6 to secure a win, his next start against the Seibu Lions on August 13 was challenging, as he allowed eight runs (five earned) and was ejected after hitting a batter with a pitch following a warning. On August 21, he allowed four runs in four innings against the SoftBank Hawks, resulting in a no-decision. He was then removed from the active roster on August 22 and did not make any further appearances in the first team for the rest of the season. For the year, Tajima made 10 starts, finishing with 3 wins and 4 losses and an ERA of 3.44. In the offseason, his salary was reduced by 2.00 M JPY to an estimated 18.00 M JPY.
2.2.3. 2020 Season
The 2020 season was shortened to 120 games due to the COVID-19 pandemic, with the start of the season delayed until June. Tajima returned to the Opening Day rotation for the first time in two years. In his first start of the season on June 19 against the Tohoku Rakuten Golden Eagles, he pitched five innings, allowing three hits and three walks for one earned run, but received a no-decision. He continued to pitch well, allowing only one run in 6.2 innings against the Chiba Lotte Marines on June 27, but again, the decision did not go his way. On July 4, he secured his first win of the season against the Seibu Lions, pitching seven innings and allowing three runs. Despite consistently good pitching, he often lacked run support from the offense, leading to a period where his ERA was the second-best in the league, but he had only one win. On September 9, he suffered his fourth consecutive loss against the Seibu Lions. However, in his next start on September 15 against the Rakuten Golden Eagles, he pitched a masterful nine-inning, two-hit, scoreless game, earning his first career complete-game shutout without allowing any runner to reach second base. Tajima remained in the starting rotation for the entire season, reaching the regulation innings pitched for the first time in his career. He made 20 starts, finishing with 4 wins and 6 losses and an ERA of 4.05. Although he initially held out during contract negotiations on December 7, he signed a new contract on December 17 after the club offered a significant increase, raising his salary by 24.00 M JPY to an estimated 42.00 M JPY.
2.2.4. 2021 Season
In 2021, Tajima once again secured a spot in the Opening Day rotation. Although he was removed from the active roster twice in the first half and twice in the second half for longer rest periods (approximately 10 days between starts), he played a consistent role in the starting rotation throughout the season. He reached the regulation innings pitched for the second consecutive year, making 24 starts and finishing with 8 wins and 8 losses and an ERA of 3.58. His contributions were vital to the team's first league championship in 25 years. In the postseason, he started Game 2 of the Climax Series Final Stage against the Chiba Lotte Marines, a team he had a favorable record against (3 wins, 1 loss, 2.37 ERA) during the regular season. He pitched six scoreless innings, earning the win. In Game 3 of the Japan Series against the Tokyo Yakult Swallows, he pitched 4.2 innings, allowing one earned run, though he received a no-decision. In the offseason, his salary was increased by 38.00 M JPY to an estimated 80.00 M JPY.
2.2.5. 2022 Season
For the third consecutive year, Tajima made the Opening Day rotation in 2022, starting the season's home opener against the Rakuten Golden Eagles. He pitched well, allowing one run over six innings, but received a no-decision. Despite consistent strong performances, he often lacked run support or saw leads lost by the bullpen. By May 13, after pitching seven innings with two runs allowed against the Chiba Lotte Marines, he was still winless with two losses in six starts. He finally secured his first win of the season on May 20 against the Rakuten Golden Eagles, pitching seven scoreless innings. After a couple of challenging starts, he was removed from the active roster on June 4. After re-evaluating his pitching form, he returned on June 22 against the SoftBank Hawks following an 18-day break, pitching a complete nine-inning, four-hit, seven-strikeout, scoreless game, marking his second career shutout and first without issuing a walk. Due to scheduling (including three more roster removals for rest and one 21-day break due to a rainout), he had fewer starting opportunities than usual and did not reach the regulation innings pitched, falling short by 18 innings. However, he finished the regular season on an impressive eight-game winning streak. In 20 starts, he recorded 9 wins and 3 losses with an excellent ERA of 2.66, significantly contributing to the team's consecutive league championship. In the postseason, he started Game 3 of the Climax Series Final Stage against the SoftBank Hawks and Game 5 of the Japan Series against the Yakult Swallows. In the offseason, his salary was increased by 30.00 M JPY, making him one of three Orix players to reach the 100.00 M JPY mark, with an estimated salary of 110.00 M JPY.
2.2.6. 2023 Season
In 2023, Tajima once again began the season in the Opening Day rotation, making his first start against the SoftBank Hawks in the home opener. Despite holding the Hawks to one hit through five innings, he surrendered four runs on two home runs in the sixth inning, finishing with 6 innings, 5 hits, 1 walk, 8 strikeouts, and 4 earned runs, resulting in a loss. He secured his first win of the season on April 12 against the Rakuten Golden Eagles, pitching 6.1 innings with 1 earned run allowed. On May 10, he again pitched well against the Eagles, allowing two runs over 8.1 innings for another win. He showcased his "Rakuten Killer" reputation, achieving a 10-game winning streak against them, which was eventually broken on September 30 when he allowed 4 runs (1 earned) over 6 innings in a loss, due in part to three team errors. On June 6, he was removed from the active roster due to stiffness in his left forearm. After a rehabilitation start in the minor leagues on June 23, he was scheduled to return to the first team on August 3 for his birthday, but he was forced to withdraw due to a fever. He finally made his return to the first team on August 30 against the SoftBank Hawks, pitching five innings and allowing three runs to earn a victory. For the season, Tajima made 13 appearances, recording 6 wins and 4 losses with an ERA of 3.09. In the postseason, he started Game 2 of the Climax Series Final Stage against the Chiba Lotte Marines, allowing four runs over six innings. In Game 5 of the Japan Series against the Hanshin Tigers, he delivered a strong performance, pitching seven scoreless innings. Notably, in the fifth inning of that game, he also recorded his first professional hit. In the offseason, his salary was reduced by 15.00 M JPY to an estimated 95.00 M JPY.
2.2.7. 2024 Season
In 2024, Tajima was again part of the Opening Day rotation, despite missing one pre-season start due to left shoulder conditioning issues. His season debut came in the third game of the season against the SoftBank Hawks, where he pitched five innings, allowing one run for a no-decision. His first win of the season came on April 9 against the Rakuten Golden Eagles, after pitching five innings, allowing two runs on six hits and two walks, though his pitch count was high. However, he struggled with control thereafter, often creating difficult situations with walks. After five starts, where he recorded 2 wins and 1 loss with a 2.74 ERA, but allowed 22 hits and 11 walks in 23 innings, he was removed from the active roster on May 2. He returned to the starting rotation on May 17 against the Rakuten Golden Eagles. As he himself admitted, he felt he was "allowed to stay in the first team rather than staying on his own terms" due to frequent roster changes, being removed four times and re-registered four times. He continued to fill a key role in the starting rotation due to injuries to Hiroya Miyagi and Kohei Azuma, and the struggles of Shunpeita Yamashita. In his final regular-season start on October 1 against the SoftBank Hawks, despite receiving six runs of support by the third inning, he was pulled after allowing six runs in 4.2 innings. After the game, manager Satoshi Nakajima commented on Tajima's performance, stating, "Regarding finishing games, he wins as much as he loses. A pitcher who can close out games firmly suppresses key moments. That's what I've seen from ace-class pitchers so far. In that sense, considering his ability and pitch quality, it's a waste." For the season, Tajima made 21 starts, finishing with an ERA of 3.68 and a record of 6 wins and 8 losses, marking the first time in three years he did not have more wins than losses. In the offseason, his salary was increased by 5.00 M JPY to an estimated 100.00 M JPY, reaching the 100.00 M JPY mark again.
3. Playing Style
Daiki Tajima's pitching style is characterized by an unconventional delivery and a versatile pitch repertoire. His approach to pitching has evolved over his career, particularly in response to injuries, showcasing a thoughtful philosophy towards the game.
3.1. Pitch Repertoire and Style
Tajima's primary pitch is his fastball, which clocks in at a maximum speed of 96 mph (154 km/h). Complementing his fastball, he utilizes a variety of breaking and off-speed pitches, including a cut fastball, two-seam fastball, forkball, slider, changeup, and curveball. He employs these pitches strategically to keep batters off balance and induce swings and misses.
3.2. Pitching Form and Evolution
Tajima possesses an unconventional three-quarter delivery that is close to a sidearm motion. His form involves pointing his right arm directly towards the batter during his weight transfer. While his body opens early, his wide range of motion around the shoulder blades allows his left arm to lag behind, creating a deceptive and difficult-to-read release point. Former JR East manager Tetsuya Horii initially expressed concerns about Tajima's control and injury risk due to his unique form. In his first year with JR East (2015), efforts were made to shorten his takeback. After suffering a left elbow injury in his rookie professional season (2018), Tajima reflected that he was over-relying on his upper body, simply "swinging his arm." This experience prompted a significant adjustment in his mechanics. He shifted his focus to a lower-body driven delivery, aiming for a "de-stress pitching" approach to generate powerful fastballs with less perceived effort. This philosophical shift in his mechanics was a crucial step in his recovery and continued development. Throughout his career, Tajima has shown a willingness to experiment with his pitching mechanics. In the 2024 season, he was observed trying different wind-ups, including pitching from the set position with no runners on base in one game, a no-wind-up in another, and even reverting to a full wind-up in subsequent starts, indicating his continuous search for optimal performance.
3.3. Pitching Philosophy
Tajima's approach to baseball is notably individualistic. He has stated that he did not watch much professional baseball during his amateur days, and he adheres to a personal policy of not setting specific pitchers as role models or batters as rivals. Instead, he prefers to maintain his own pace and unique style, believing that "if you only stick to one form, you can't keep pitching." He also acknowledges the importance of self-awareness, stating, "If you are insensitive, you cannot play for long," recognizing the need for constant adjustment based on his own condition and the game situation.
4. Personal Life
Daiki Tajima is known by the nickname "Taji." He is an ardent fan of Japanese idol groups Nogizaka46 and Sakurazaka46 (formerly Keyakizaka46). His favorite member is Neru Nagahama, a former member of Keyakizaka46. Their shared interest even led to a unique co-appearance on the TV Tokyo show "Keyakitte, Kakenai?" on March 5, 2018, where Nagahama and Yuuka Sugai visited Tajima during his spring training camp in Miyazaki. During his corporate baseball days, he even had the kanji character "欅" (Keyaki) embroidered on his glove, demonstrating his strong affinity for the group. For his entrance music, he has used "Eccentric" (2018-2019) and "Glass wo Ware!" (2018-2019) by Keyakizaka46, and "Never Change" by DOBERMAN INFINITY (2020-present).
5. Career Statistics and Records
Daiki Tajima's career as a professional baseball player is marked by several significant achievements and consistent performance, as reflected in his pitching and fielding statistics.
5.1. Notable Firsts
- First Appearance, First Start, First Win, First Start Win:** March 31, 2018, vs. Fukuoka SoftBank Hawks (Game 2) at Fukuoka PayPay Dome. He pitched 5 innings, allowing 1 hit and 1 earned run.
- First Strikeout:** March 31, 2018, vs. Fukuoka SoftBank Hawks (Game 2) at Fukuoka PayPay Dome, striking out Kenta Imamiya swinging in the 1st inning.
- First Complete Game, First Complete Game Win, First Shutout Win:** September 16, 2020, vs. Tohoku Rakuten Golden Eagles (Game 14) at Hotto Motto Field Kobe. He pitched 9 innings, allowing 2 hits and no runs.
- First At-Bat:** June 10, 2018, vs. Tokyo Yakult Swallows (Game 3) at Meiji Jingu Stadium, striking out looking against Yasuhiro Ogawa in the 3rd inning.
- First Hit:** November 2, 2023, vs. Hanshin Tigers (Japan Series Game 5) at Kyocera Dome Osaka, an RBI single off Takumi Akiyama in the 5th inning.
5.2. Annual Pitching Statistics
| Year | Team | GP | GS | CG | SHO | BB% | W | L | SV | HLD | W-L% | BF | IP | H | HR | BB | IBB | HBP | SO | WP | BK | R | ER | ERA | WHIP |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2018 | Orix | 12 | 12 | 0 | 0 | 0 | 6 | 3 | 0 | 0 | .667 | 291 | 68.2 | 60 | 9 | 24 | 0 | 4 | 69 | 2 | 0 | 33 | 31 | 4.06 | 1.22 |
| 2019 | 10 | 10 | 0 | 0 | 0 | 3 | 4 | 0 | 0 | .429 | 219 | 49.2 | 48 | 4 | 20 | 0 | 1 | 40 | 1 | 0 | 26 | 19 | 3.44 | 1.37 | |
| 2020 | 20 | 20 | 1 | 1 | 0 | 4 | 6 | 0 | 0 | .400 | 512 | 122.1 | 102 | 14 | 42 | 0 | 7 | 89 | 2 | 0 | 57 | 55 | 4.05 | 1.18 | |
| 2021 | 24 | 24 | 0 | 0 | 0 | 8 | 8 | 0 | 0 | .500 | 608 | 143.1 | 137 | 10 | 48 | 1 | 5 | 135 | 4 | 1 | 62 | 57 | 3.58 | 1.29 | |
| 2022 | 20 | 20 | 1 | 1 | 1 | 9 | 3 | 0 | 0 | .750 | 513 | 125.0 | 115 | 12 | 37 | 0 | 2 | 92 | 3 | 1 | 41 | 37 | 2.66 | 1.22 | |
| 2023 | 13 | 13 | 0 | 0 | 0 | 6 | 4 | 0 | 0 | .600 | 338 | 81.2 | 73 | 9 | 18 | 0 | 2 | 64 | 2 | 0 | 31 | 28 | 3.09 | 1.11 | |
| 2024 | 21 | 21 | 0 | 0 | 0 | 6 | 8 | 0 | 0 | .429 | 501 | 117.1 | 121 | 10 | 34 | 0 | 2 | 87 | 4 | 0 | 51 | 48 | 3.68 | 1.32 | |
| Total: 7 years | 120 | 120 | 2 | 2 | 1 | 42 | 36 | 0 | 0 | .538 | 2982 | 708.0 | 656 | 68 | 223 | 1 | 23 | 576 | 18 | 2 | 301 | 275 | 3.50 | 1.24 | |
The statistics are accurate as of the end of the 2024 season, with bolded values indicating a league leader in that category.
5.3. Annual Fielding Statistics
| Year | Team | Pitcher | |||||
|---|---|---|---|---|---|---|---|
| G | PO | A | E | DP | FP% | ||
| 2018 | Orix | 12 | 0 | 8 | 0 | 0 | 1.000 |
| 2019 | 10 | 2 | 7 | 1 | 0 | .900 | |
| 2020 | 20 | 6 | 24 | 1 | 1 | .968 | |
| 2021 | 24 | 6 | 26 | 1 | 2 | .970 | |
| 2022 | 20 | 4 | 17 | 0 | 1 | 1.000 | |
| 2023 | 13 | 5 | 11 | 0 | 0 | 1.000 | |
| 2024 | 21 | 7 | 19 | 0 | 1 | 1.000 | |
| Total | 120 | 30 | 112 | 3 | 5 | .979 | |
The statistics are accurate as of the end of the 2024 season.
5.4. Uniform Number
- 29 (2018-present)
5.5. Entrance Music
- "Eccentric" by Sakurazaka46 (Keyakizaka46) (2018-2019)
- "Glass wo Ware!" by Keyakizaka46 (2018-2019)
- "Never Change" by DOBERMAN INFINITY (2020-present)