On the 4th, Seibu Lions announced that they have signed a contract for this season with pitcher Kosei Takahashi (28), who had been aiming to challenge the Major Leagues through the posting system.

Through the team, General Manager Hiroike commented, "We are encouraged that he chose to play for The Lions this season despite having offers to sign with a major league team. pitcher Kosei Takahashi is a very valuable asset to the team. I believe he will approach the season with strong determination, and I expect him to achieve career-high results and make a great contribution to the team's win."

Takahashi, who led Maebashi Ikuei High School (Gunma) to their first championship in the summer Koshien in his second year as their ace pitcher, joined Seibu Lions as their first overall pick in the 2014 draft. From 2021 to 2023, he recorded double-digit win for three consecutive years. The right-handed pitcher, who admires his Seibu Lions teammate Yusei Kikuchi (now with the Angels), requested permission from the team in the offseason of 2022 to potentially play in MLB. However, the team did not approve in the offseason of 2023, and in 2024, his tenth year as a professional, he gave up on his dream after a nightmare 0 wins and 11 losses. "It would definitely be a plus for baseball career. I just want to get revenge, that's all," he said, and last season he appeared in 24 games, showing signs of recovery with an 8-9 record and a 3.04 ERA. With the 2026 season approaching, when he is expected to acquire overseas free agency rights, he was given permission to challenge the dream stage.

However, among the Japanese players who used the system this offseason, Yakult 's Munetaka Murakami reached an agreement with the White Sox and Seibu Lions 's Tatsuya Imai reached an agreement with the Astros, but there was little information about Takahashi. On the 1st (2nd in Japan), the MLB official website reported under the headline "Takahashi may return to Japan in 2026" that "He received an offer from at least one team, but it may not have been enough for him to decide to move to the majors. Instead, he has signed a multi-year contract with Seibu Lions, including an opt-out clause, and as a free agent not subject to the posting system restrictions, he will be able to re-enter the majors market in the 2026 offseason."

At the Winter Meetings held last December, where managers, general managers, and agents from each team gathered to negotiate transfers, J. Wolf, Takahashi's agent at Wasserman's Office, told Sports Hochi that "I think we can get a multi-year contract, but there's also a possibility he'll ultimately return to Seibu Lions." However, his dream isn't over. Seibu manager Seibu Lions has stated that if Takahashi stays, he will include him as a candidate for the opening day pitcher this season. It's possible that he could prove himself in Japan again and then make his move overseas when the time is right.