At the time, Iyama was the fourth youngest professional behind Cho Chikun, Utaro Hashimoto and Satoshi Yuki.

[7] He met his rival, Daisuke Murakawa, a fellow player from the Kansai region, in the final section of the 30th Shinjin-O.

[8] Iyama won the first major game of his career when he defeated Cho U by resignation in the 20th Agon Cup.

The previous holder of the record was Cho Chikun, who won the Shin-Ei, a tournament open to young players only, at 17 years.

[16] Three months after his unsuccessful Honinbo league bid, Iyama participated in the first edition of the Daiwa Cup, an internet tournament.

Taking black, Iyama lost to Keigo Yamashita by 1.5 points and was unable to challenge title-holder Rin Kono.

[19] Iyama qualified for his first international tournament, the 21st Fujitsu Cup, by defeating Kanketsu Rin and Michihiro Morita in the preliminary stages.

[20] In the main tournament, Iyama defeated Taiwanese representative Zhou Junxun, but lost to Korea's Lee Sedol in the second round.

[21][22] In March 2008, Iyama participated in the 1st Yugen Cup, a tournament pitting veteran professionals against newly promoted youngsters.

He broke a record held by Cho Chikun, who challenged for the Oza title in 1976 at the age of 20 years.

[30] In March 2008, Iyama participated in the inaugural BC Card Cup as one of Japan's two representatives, Cho Chikun being the other.

Chikun was knocked out in the first round by Paek Hongsuk, but Iyama won two games in a row against Kim Seongjae and On Sojin.

Iyama and partner Xie Yimin lost to Naoki Hane and Keiko Kato in the final of the Rengo Cup.

[35] Iyama also reached the challenger final of the 34th Gosei, but eventually lost to Satoshi Yuki by 1.5 points.

[48] In October 2010, Iyama was invited to the World Meijin tournament along with Gu Li and Lee Chang-ho.

In January 2017, Iyama was awarded the Shusai Prize, which honors the outstanding player of the previous year.

In February 2017, Iyama was awarded the Kido Prize for "Most outstanding player" for winning all top seven titles.