Matsui Kazuo (松井 稼頭央) is a Japanese retired professional baseball player who played as a shortstop and is the current manager of the Saitama Seibu Lions. He competed in multiple Pro Sportsman No. 1 tournaments, and in Pro Sportsman No. 1 1997 (his first appearance), Matsui earned the 1st place of the entire competition. However, since that particular newcomer performance, Matsui struggled against the tide as he was unable to catch up with his fellow competitors Ogata Koichi and Kane Kosugi for winning the 1st place in succeeding Pro Sportsman No.1 competitions.