However, after winning the jūryō championship in September 2005 with a strong 14–1 record, his fortunes began to turn and after some initial struggles, he rose steadily through the ranks of makuuchi.

His first big success came in January 2007 when ranked at maegashira 9 he finished as runner up to yokozuna Asashōryū with an outstanding 12–3 record and earned his first special prizes for Fighting Spirit and Technique.

[1] However, before the tournament began he sprained his knee and ankle ligaments in a practice session with Asashōryū at his stable[2] and could only manage four wins in his san'yaku (titled rank) debut.

He was one of seven wrestlers who NHK commentator Shūhei Nagao (the former Mainoumi) in 2008 called the "Seven Samurai" and identified as "holding the key" to a Japanese resurgence in sumo, which was dominated by foreigners in the top ranks.

He finished with ten wins and another Outstanding Performance prize, and Kotoshogiku's losing record meant Toyonoshima was promoted to sekiwake for the September tournament, becoming the first wrestler from Tokitsukaze stable to reach the rank since Kurama in 1978.

Despite being doubled over in pain, Toyonoshima managed to bow to Kaiō and left the dohyō unassisted, until he was safely back in the dressing area, where medical attention appeared to be prompt.

The online-edition of the Yomiuri Shimbun reported that Toyonoshima was diagnosed with left-elbow sprain" and he was forced to forfeit the next day's scheduled bout against Kotoshōgiku.

[4] Later news reports indicated that the Japan Sumo Association doctors told the 25-year-old rikishi to take a six-week medical leave,[5] and that Toyonoshima would bow out of the remainder of the 2009 Hatsu basho at the Ryōgoku Kokugikan in Tokyo.

Toyonoshima returned to action in the March tournament in Osaka with his elbow strapped, but secured a winning record of 8–7 on the final day.

He produced his best performance of the year in November, a promising 11–4 score which won him his second Technique prize and opened up the possibility of promotion back to san'yaku in January 2010.

He lost to Hakuhō in a playoff for the yūshō on the final day, narrowly failing to become the first wrestler ever to win back-to-back jūryō and makuuchi championships (and the first Japanese-born winner of a top division tournament since 2006), but he received special prizes for Fighting Spirit and Technique.

He made a poor start to the January tournament losing seven of his first eight matches, but he recovered to earn his 8–7 majority of wins on the final day.

He had a fine tournament in March, beating the ōzeki Kotoshōgiku and Kotoōshū and sharing the Technique prize, which returned him immediately to sekiwake.

In the May 2012 basho he defeated Hakuhō for just the second time in the top division, sending the yokozuna crashing to his fourth loss of the tournament.

He missed the July 2016 tournament after undergoing surgery for a left Achilles tendon rupture which occurred in training and as a result was demoted to jūryō for the first time since 2010.

[11] He had reportedly been making payments towards the Nishikijima name previously intended for his former stablemate Shimotori before he was forced to quit sumo, but he was ultimately unable to acquire it, and the stock went to Asasekiryū instead.

Toyonoshima was married to pop singer Sunaho Takeuchi in February 2011 and the wedding reception was held that October in Tokyo's Metropolitan Hotel with around 600 guests attending.