On the 4th, Seibu Lions announced that they had reached a contract agreement with Kosei Takahashi, who had been aiming to challenge the Major Leagues through the posting system. Tatsuya Imai will leave the team after reaching a contract agreement with the Houston Astros through the posting system, but with Takahashi continuing to play for Seibu Lions this season, the loss to their starting rotation has been minimized.

Takahashi pitched 148 innings in 24 games last season, going 8-9 with ERA of 3.04, and was part of the starting rotation. The team also includes Tomoichiro Sumida, who, along with Tatsuya Imai, recorded a team-high 10 wins (10 losses) last season with ERA of 2.59; Chihiro Sumida Yutaro Watanabe, who pitched 134 innings and earned 7 wins, although he did not reach the required number of innings pitched pitched Kaima Taira, who is expected to return to starting closer; Kaito Yoza had 6 wins last season; Natsuki Takeuchi, the 2024 Rookie of the Year; and Shinya Sugai, who gained experience in the first team last season.

Furthermore, the team has acquired a new foreign pitcher Allan Winans a skilled right-hander. Team General Manager Koji Hiroike commented, "We envision pitch in inning while making use of defense to get outs, but he recorded a high strike out rate and a low BB rate in Triple-A, so we are very much looking forward to seeing how he pitch against NPB hitter."

Having Takahashi play for Seibu Lions again this season is a huge advantage, as it means they have a reliable starter. Starting the new season without two ace pitchers like Imai and Takahashi makes a big difference. The void left by Imai's 10 wins and 163 2/3 innings pitched last season can be more than filled by the growth of young players such as Taira, who is expected to return to the starting rotation, Takeuchi, who had a poor season last year, and promising young players Watanabe Yu and Sugai. There is a feeling that they will be able to form a strong starting rotation once again.