Koki Yamaguchi
Koki Yamaguchi
Born: August 18, 2000
Primary Position: Outfield
All Position(s) Played: 1B
Bats: Right
Throws: Right
Height: 5'11"
Weight: 187
Career: 2021-2025
Koki Yamaguchi compiled a career batting average of .224 with 34 home runs and 114 RBI in his 266-game career with the Chiba Lotte Marines. He began playing during the 2021 season and last took the field during the 2025 campaign.
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Batting:
| Year | Level | Lg | Team | GP | PA | AB | R | H | 2B | 3B | HR | RBI | SB | CS | BB | SO | BA | OBP | SLG | OPS | TB | DP | HBP | SH | SF | IBB |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2021 | Foreign Major | JPPL | Chiba Lotte Marines | 78 | 228 | 203 | 20 | 42 | 3 | 1 | 9 | 20 | 0 | 1 | 25 | 53 | .207 | .294 | .365 | .658 | 74 | 5 | 0 | 0 | 0 | 0 |
| 2022 | Foreign Major | JPPL | Chiba Lotte Marines | 102 | 349 | 321 | 40 | 76 | 14 | 0 | 16 | 57 | 1 | 0 | 23 | 84 | .237 | .295 | .430 | .725 | 138 | 8 | 4 | 0 | 1 | 0 |
| 2024 | Foreign Major | JPPL | Chiba Lotte Marines | 51 | 181 | 170 | 10 | 34 | 8 | 0 | 2 | 13 | 1 | 0 | 10 | 30 | .200 | .249 | .282 | .531 | 48 | 6 | 1 | 0 | 0 | 0 |
| 2025 | Foreign Major | JPPL | Chiba Lotte Marines | 35 | 112 | 106 | 11 | 27 | 2 | 0 | 7 | 24 | 1 | 1 | 5 | 37 | .255 | .286 | .472 | .757 | 50 | 3 | 0 | 0 | 1 | 0 |
| Totals | 266 | 870 | 800 | 81 | 179 | 27 | 1 | 34 | 114 | 3 | 2 | 63 | 204 | .224 | .284 | .388 | .671 | 310 | 22 | 5 | 0 | 2 | 0 |
Fielding:
| Year | Level | Lg | Team | Pos | GP | PO | A | E | DP | Fld% | RF/G |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2021 | Foreign Major | JPPL | Chiba Lotte Marines | OF | 24 | 31 | 0 | 1 | 0 | .969 | 1.292 |
| 2021 | Foreign Major | JPPL | Chiba Lotte Marines | 1B | 21 | 120 | 10 | 1 | 6 | .992 | 6.190 |
| 2022 | Foreign Major | JPPL | Chiba Lotte Marines | 1B | 44 | 309 | 21 | 0 | 26 | 1.000 | 7.500 |
| 2022 | Foreign Major | JPPL | Chiba Lotte Marines | OF | 33 | 42 | 2 | 0 | 0 | 1.000 | 1.333 |
| 2024 | Foreign Major | JPPL | Chiba Lotte Marines | OF | 47 | 76 | 1 | 2 | 0 | .975 | 1.638 |
| 2024 | Foreign Major | JPPL | Chiba Lotte Marines | 1B | 1 | 6 | 1 | 0 | 1 | 1.000 | 7.000 |
| 2025 | Foreign Major | JPPL | Chiba Lotte Marines | 1B | 9 | 55 | 4 | 0 | 4 | 1.000 | 6.556 |
| 2025 | Foreign Major | JPPL | Chiba Lotte Marines | OF | 7 | 15 | 0 | 0 | 0 | 1.000 | 2.143 |
| Totals | 109 | 303 | 16 | 4 | 11 | .988 | 2.927 |
Minor League Service:
| Year | Level | League | Team | Affiliation | First Appearance | Final Appearance |
|---|---|---|---|---|---|---|
| 2021 | Foreign Major | Japan Pacific | Chiba Lotte Marines | |||
| 2022 | Foreign Major | Japan Pacific League | Chiba Lotte Marines | |||
| 2023 | Foreign Major | Japan Pacific League | Chiba Lotte Marines | |||
| 2024 | Foreign Major | Japan Pacific League | Chiba Lotte Marines | |||
| 2025 | Foreign Major | Japan Pacific League | Chiba Lotte Marines |
Persons data from the Chadwick Baseball Bureau are Copyright Chadwick Baseball Bureau, and are made available under the Open Data Commons Attribution License.

