"Lost Man/Sailing Day" (ロストマン/sailing day, Rosutoman/seiringu dei) is the sixth single by Bump of Chicken. The title tracks are from the album Yggdrasil (ユグドラシル). "Lost Man" is the song that writing took time most from summer of 2002 to the end of the year. Also "Sailing Day" featured as the end theme to the animated movie One Piece The Movie: Dead End no Bōken.