Yokotani was born in Kyoto Prefecture on May 10, 1952. After graduating from Hosei University, he joined Japan Soccer League club Hitachi in 1975. The club won the 1975 Emperor's Cup and 1976 JSL Cup. He moved to Division 2 club All Nippon Airways in 1984. In 1984, the club was promoted to Division 1. He retired in 1986.