Seibu Lions announced that Mitsuki Ono, a Saitama native who won a bronze medal in the women's halfpipe snowboarding event at the Milan-Cortina Olympics, will throw the opening pitch as a guest at the home opening game on March 31st.

Ono commented through the team, "Hello everyone, The Lions fans. I'm Mitsuki Ono. I'm so happy to have been asked to participate in the opening game of Saitama Seibu Lions, my hometown team! It's my first time throwing the first pitch, so I'm a little nervous, but I'll throw it with all my might and enjoy it to the fullest!"

Also, at the home opening ceremony on the same day, pianist Shinya Kiyozuka will perform a song he composed for The Lions, "WE ARE ONE," and the national anthem, "Kimigayo." "WE ARE ONE" has been used as the song when players run out onto ground since the 2021 season.