|Hanshin Tigers – No. 50|
|Born: December 11, 1993|
|2016, for the Hanshin Tigers|
|Career statistics |
|Earned Run Average||3.28|
Early baseball career
Kōyō played ball for the Terao Dolphins as a fifth-grader in primary school, and went on to pitch for Namamugi Junior High. He became the ace pitcher of Kawasaki Kikoka High School in Kanagawa, but his team never made it to the national tournament.
He entered Teikyo University where he was a regular starter in the Tokyo Metropolitan Area University Baseball League. Despite having undergone right elbow surgery in his third year, he pitched spectacularly the following year where he led the league in wins (6), and was awarded Best Nine. After four years and 37 game appearances, he finished 15–9 with a 1.91 ERA.
He was the Tiger's 5th round pick during the 2015 professional draft. He signed a 40 million yen contract with Hanshin, for an estimated annual salary of 7.2 million yen. He was assigned jersey number 50.
While he joined the main squad during spring camp and got a shot at pitching during the pre-season game against the Marines, he struggled with control as he walked the first 3 batters he faced, and ended up giving up 2 runs in 2 innings of relief.
He debuted as a starter in the June 1 away game against the Eagles, as a last minute replacement for the scheduled starter Yuya Yokoyama who suddenly experienced shoulder pain at the time. Despite walking 4 and hitting 1 batter, he completed 5 innings and only allowed a sole run, thus grabbing the win. He became the first right-handed Hanshin pitcher to win his first official start since Minoru Murayama on 1959, and the third rookie pitcher in NPB history to win his first start during Inter-league play.
His next start was on July 7 in Tokyo Dome, where he shut down the Giants by pitching 7 perfect innings while allowing only a single hit. After this, he became a regular in the Tiger's pitching rotation. But despite a strong start, he lost momentum during mid-season, and he finished the season with only 4 wins out of 13 games with a 3.29 ERA. While his win-loss percentage might be unimpressive, he only surrendered a single home run out of 289 at bats.
During the post-season break, he was selected to join the national team to pitch in the Asia Winter League tournament in Taiwan. He notched 2 wins and 1 save in 4 games (1.69 ERA), and was awarded the league's best pitcher, also won by fellow Hanshin pitcher Yuta Iwasada in the previous year.
A sidewinder and sometimes submarine pitcher, Aoyagi throws a shuuto in the 130-145kph range as his main pitch, alternating with a four-seam in the high 130s (maxed at 147 kph) or a slider, with the occasional changeup.. He was clocked at 6.8 seconds at the 50 meter dash.
Aoyagi started throwing from a three-quarters delivery when he started pitching in grade school. At first, the team manager tried to fix his mechanics, but eventually decided to encourage him to keep throwing from the side.
Aoyagi is also an avid manga fan. When he first joined the Tigers, he moved into their dormitory with about 300 volumes of the Weekly Shōnen Magazine. When he played in the 2016 Winter League, he kept posting sad tweets of not being able to read the magazine in Taiwan. Kodansha, the manga's publisher, read about Aoyagi's tweets, and promised him that they will reserve copies of the magazine that he wasn't able to read while overseas. The company sent 3 weeks worth of the magazine to the Tiger's camp when Aoyagi returned to Japan.  Kodansha is thinking about naming him their manga publicity ambassador.
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