Due to injuries and underperformance, he rarely appeared in the team's games and was nicknamed "the phantom pitcher" by zealous Osaka Gas fans.

In 2004, together with soon-to-be teammates Ryo Watanabe and Yasutomo Kubo, Nōmi played for the national team in the 22nd Haarlem Baseball Week where Japan finished 3rd.

2007 With ace Kei Igawa leaving for Major League Baseball, Hanshin was faced with a shortage of starting pitchers.

Nōmi returned in August where he won 3 starts, including a complete game, but he suffered a setback on September 11 by surrendered 7 runs in 4 innings.

Despite his reliability on the mound, he couldn't record a win during his starts early in the season due in part to a lack of run support.

He managed to rebound in his start against the Giants on July 19, where he pitched 9 innings with only 2 hits surrendered and 12 strikeouts, which earned him his first win of the season.

On May 3, he tied Kobayashi's record of 8 consecutive wins against the Giants but failed to surpass it when he took the loss on June 26 upon surrendering 3 runs in 5 innings.

Nōmi's form improved in August, and he steamrolled through September where he won 3 of his 4 starts with an ERA of 0.55, earning him another MVP of the month award.

2014 Nōmi again opened the season with a game against the Giants, but he allowed 10 earned runs in 5 innings as the Tigers lost an early 4-run lead against their arch rivals.

[14] Despite these achievements, Nōmi finished the season with his worst record of 9–13 (most losses in the league) due in part to a lack of stability in the mound.

Nōmi again delivered a quality start in the deciding game of the CS final stage, where he allowed only 2 runs in 5 innings and secured the Tigers' spot in the Japan Series, their first participation since 2005.

[16] Nōmi earned his domestic free agency option during offseason but he decided to stay with the Tigers and inked a 3-year contract for an estimated 450 million yen.