A defender, Ihara was captain of the Japan national team for more than a decade in the 1990s, together with striker Kazuyoshi Miura and Brazilian-born midfielder Ruy Ramos.

Ihara's long standing record of 122 national team appearances was surpassed by Yasuhito Endo on October 16, 2012.

He spent most of his career with Yokohama F. Marinos and formed a key defensive partnership with the flamboyant Tsuyoshi Kitazawa at club level.

On January 27, 1988, when Ihara was a University of Tsukuba student, he debuted for Japan national team against United Arab Emirates.

During the 1998 World Cup in France, the veteran sweeper's experience was crucial to Japan's survival in their first World Cup appearance, forming a flat back three defence with strong centre-back Yutaka Akita as well as speedy fullbacks Eisuke Nakanishi (or strong centre-back Norio Omura).

After a horrible three years of being at the bottom half of the table in the J2 League, Avispa Fukuoka then hired Ihara as their coach, replacing the former Marijan Pušnik.

Under Ihara, then club went on to win 24 games out of 42 and collected a total of 82 points, ending their regular season in third place.