On the 10th, Seibu announced that they would accept pitcher Tatsuya Imai 's challenge to transfer to Major League Baseball using the posting system, after he expressed his intention to do so.

Team General Manager Hiroike Koji commented, "We decided that now was the time, and have allowed him to take on the challenge of MLB. We have accepted his consistent and strong desire to play baseball in America, and as a team we have respected that desire. Since he is taking on the challenge, we want him to show us how he thrives in America. Imai has made great contributions to the team in recent years, so although his departure will have an impact, we will continue to fight by focusing on the development of young players and strengthening our team structure."

Imai expressed his gratitude to the team through the team, saying, "I'm grateful that my request was accepted. I'm very grateful that they took many things into consideration during our many discussions and spent a long time making their decision. Every year until now, I've played with the aim of winning the league championship and becoming the best in Japan, and that feeling remains the same even though I've changed teams. I'm determined to win, and I'll do my best to pitch to be a help to the team."