Shirai was born in Kumamoto Prefecture on April 18, 1966.
[1] After graduating from Kyoto Sangyo University, he joined Tanabe Pharmaceutical in 1989.
However he could hardly play in the match behind Kenji Honnami and Hayato Okanaka.
However he came back as player in March 2002 because multiple goalkeepers were injured.
[2] This biographical article related to a Japanese association football goalkeeper is a stub.