Sekiguchi was born in Saitama on October 29, 1954. After graduating from high school, he joined his local club Mitsubishi Motors in 1973. In 1973, the club won the champions Japan Soccer League and Emperor's Cup. In 1978, the club won all three major title in Japan; Japan Soccer League, JSL Cup and Emperor's Cup. In 1980s, the club also won 1980 Emperor's Cup, 1981 JSL Cup and 1982 Japan Soccer League. He retired in 1988. He played 153 games and scored 36 goals in the league.