| Japan - NPB Reserve League | 2021/07/23 07:00 | Seibu Lions - Reserves v Yomiuri Giants - Reserves | W | 9-4 |
| Japan - NPB Reserve League | 2021/04/22 04:00 | Seibu Lions - Reserves v Yomiuri Giants - Reserves | L | 0-14 |
| Japan - NPB Reserve League | 2021/03/24 04:00 | Yomiuri Giants - Reserves v Seibu Lions - Reserves | W | 1-2 |
| Japan - NPB Reserve League | 2021/03/23 04:00 | Yomiuri Giants - Reserves v Seibu Lions - Reserves | W | 0-1 |
| Japan - NPB Reserve League | 2020/10/30 03:30 | Yomiuri Giants - Reserves v Seibu Lions - Reserves | D | 2-2 |
| Japan - NPB Reserve League | 2020/10/04 03:30 | Yomiuri Giants - Reserves v Seibu Lions - Reserves | D | 0-0 |
| Japan - NPB Reserve League | 2020/10/02 04:00 | Yomiuri Giants - Reserves v Seibu Lions - Reserves | L | 6-4 |
| Japan - NPB Reserve League | 2020/09/12 04:00 | Seibu Lions - Reserves v Yomiuri Giants - Reserves | D | 0-0 |
| Japan - NPB Reserve League | 2021/07/23 07:00 | Seibu Lions - Reserves v Yomiuri Giants - Reserves | W | 9-4 |
| Japan - NPB Reserve League | 2021/07/22 04:00 | Yakult Swallows - Reserves v Seibu Lions - Reserves | W | 2-3 |
| Japan - NPB Reserve League | 2021/07/20 08:45 | Yakult Swallows - Reserves v Seibu Lions - Reserves | L | 4-3 |
| Japan - NPB Reserve League | 2021/07/05 08:45 | Nipponham Fighters - Reserves v Seibu Lions - Reserves | W | 6-8 |
| Japan - NPB Reserve League | 2021/06/17 04:00 | Nipponham Fighters - Reserves v Seibu Lions - Reserves | L | 2-1 |
| Japan - NPB Reserve League | 2021/04/22 04:00 | Seibu Lions - Reserves v Yomiuri Giants - Reserves | L | 0-14 |
| Japan - NPB Reserve League | 2021/03/26 03:54 | Yokohama Bay Stars - Reserves v Seibu Lions - Reserves | W | 6-8 |
| Japan - NPB Reserve League | 2021/03/24 04:00 | Yomiuri Giants - Reserves v Seibu Lions - Reserves | W | 1-2 |
| Japan - NPB Reserve League | 2021/07/23 07:00 | Seibu Lions - Reserves v Yomiuri Giants - Reserves | L | 9-4 |
| Japan - NPB Reserve League | 2021/07/05 07:00 | Rakuten Eagles - Reserves v Yomiuri Giants - Reserves | L | 6-5 |
| Japan - NPB Reserve League | 2021/06/29 02:39 | Chiba Lotte Marines - Reserves v Yomiuri Giants - Reserves | L | 6-4 |
| Japan - NPB Reserve League | 2021/06/24 07:00 | Yakult Swallows - Reserves v Yomiuri Giants - Reserves | W | 0-3 |
| Japan - NPB Reserve League | 2021/06/22 02:00 | Yakult Swallows - Reserves v Yomiuri Giants - Reserves | L | 8-2 |
| Japan - NPB Reserve League | 2021/04/22 04:00 | Seibu Lions - Reserves v Yomiuri Giants - Reserves | W | 0-14 |
| Japan - NPB Reserve League | 2021/04/08 04:00 | Chiba Lotte Marines - Reserves v Yomiuri Giants - Reserves | L | 9-0 |
| Japan - NPB Reserve League | 2021/03/26 04:00 | Nipponham Fighters - Reserves v Yomiuri Giants - Reserves | L | 3-2 |