[1] His success was short-lived, however, as Kagoshima Jitsugyo matched up with powerhouse Yokohama Senior High School (the East Kanagawa champions) in the second round.

As a player who was born in the 1980 Japanese academic year and participated in the 1998 Summer High School Baseball Championship, Sugiuchi is considered a member of the "Matsuzaka Generation".

Nevertheless, Sugiuchi was named to the Japanese national team to play in the upcoming 2000 Sydney Olympics following the tournament (Japan finished fourth).

During the off-season, he made up his mind to abandon the windup and pitch exclusively from the stretch, a decision that led to a breakout sophomore campaign in which he put up 10 wins as a member of the starting rotation alongside rookies Tsuyoshi Wada and Nagisa Arakaki.

On June 1, he gave up seven runs in the first two innings in a regular-season start against the Chiba Lotte Marines, slamming both of his fists into the dugout bench in frustration and breaking the fifth metacarpal bone on both hands.

He also beat out teammate and resident staff ace Kazumi Saito, who had a stellar season himself with a 16–1 record and a 2.92 ERA,[10] in being voted to the Eiji Sawamura and league Most Valuable Player awards.

He became the Hawks' de facto ace and went 15–6 with a 2.46 ERA, striking out 187 (the second-highest total of his career) in a career-high 197+2⁄3 innings with five complete games and three shutouts.

On October 7, the Hawks sent Sugiuchi to the mound in their regular-season game against the Tohoku Rakuten Golden Eagles in the hopes of avoiding a last-place finish in the pennant race.

He came on to replace Eagles ace Hisashi Iwakuma in the second match against Cuba in the second round, throwing three shutout innings and being credited with a save.

On April 5, in his first start of the regular season against the Orix Buffaloes, Sugiuchi struck out five over 7+2⁄3 innings to bring his career strikeout total to 1003.

[19] He was the fourth-fastest pitcher in NPB history to amass 1,000 career strikeouts (following Hideo Nomo, Kazuhisa Ishii and Yutaka Enatsu), doing so in 979+1⁄3 innings.

He had a strong outing on May 10 against the Saitama Seibu Lions, striking out 12 over eight innings and allowing just one run[20] and improving his record to 11–0 in the month of May since 2007.

Always a bit of a slow starter, he put together a fairly good April, recording a complete-game shutout of the Fighters on the 9th, and he also struck out at least nine batters in all of his starts during the month.

Despite having a rough start on May 16, an interleague game against the Tokyo Yakult Swallows, he still remained undefeated in the month, running his record to 13–0 since '07.

As 2010 started its Pacific League's end of season race between the Hawks, Lions and Marines, Sugiuchi hit a minor slump just as his team needed him most.

A much relieved Sugiuchi then famously broke down in tears at the Hero's interview as he admitted that he finally delivered during the pennant race.