In 2021, he was selected to the host nation's team for the 2020 Tokyo Olympics, where he won both the gold medal and the MVP award.

[6] After starting middle school, Yamada played for Hyōgo Itami, a team in the Japanese youth baseball organization Young League.

[9] In the Summer Koshien of his junior year, he contributed to Riseisha's first win by stealing home in the second round against Tenri High School.

In a game against Seiko Gakuin, Yamada hit a home run off Hiroaki Saiuchi, but his team would end up losing.

Kouta Inoue, who would later join the Hanshin Tigers, said that home run made him want to attend Riseisha.

[10] In the first round of the 2010 Nippon Professional Baseball (NPB) draft, Yamada was named by the Tokyo Yakult Swallows and the Orix Buffaloes.

On October 6, he hit his first professional grand slam homer off Kenta Maeda of the Hiroshima Toyo Carp.

Although he had not yet shown much power as he did not hit any homers until the end of the season, he demonstrated a good eye at the plate, recording a .354 on-base percentage, and also stole nine bases.

[19] He became the first player in NPB history to hit a first-inning lead-off homer in six consecutive months (from April to September).

[20] After being selected to his first All-Star Series by his manager's recommendation, he won the Fighting Spirit Award with two hits in the second game, including a home run.

[22] On October 6, in a game against the Yokohama DeNA BayStars, Yamada went 4-for-5 with a go-ahead grand slam in the 8th inning, which broke the single-season hits record for a Japanese right-handed batter set by Fumio Fujimura in 1950.

[27] In the middle of the season, Yakult manager Mitsuru Manaka decided to move Yamada to third in the lineup, leading to improvements in his hitting.

[citation needed] It was the first time in NPB history that a player won both the home run and stolen base titles in the same season.

[37] His season performance greatly contributed to Yakult advancing to the 2015 Japan Series against the Fukuoka SoftBank Hawks.

[38] In assessing his MVP season in October 2015, the Japan Times wrote, "Yamada had a 2015 the likes of which is seldom seen in Japanese baseball.

"[40] On December 8, during the off-season, Yakult renewed Yamada's contract, signing him for an annual salary of 220 million yen.

[47] Despite his injury, he ended the season hitting .304 with 38 home runs and 30 stolen bases, achieving a second consecutive triple three.

[citation needed] In 2017, he was the only player on the team to play a full inning in every game, despite struggling with lower body conditions.

[61] On his birthday he had a ninth inning RBI that tied the game and allowed Yakult to complete a comeback victory against DeNA.

[49][66] He finished the 2018 season with a .315 batting average, 34 home runs, and 33 stolen bases, achieving the third triple three of his career.

[96][97] He hit his 30th home run on September 26, a grand slam off Shinnosuke Ogasawara against Chunichi at Jingu Stadium,[98] marking his fifth 30-homer season.

[citation needed] As captain, he also went to the mound to inspire pitchers in a pinch and actively gave advice to younger players on the bench.

[102][103] He formed a strong duo with Munetaka Murakami who was batting fourth, and Yakult reversed their poor performances of the past two years to top the Central League standings at the end of the season.

[109] Later that game, he hit a game-tying solo home run in the top of the ninth inning to contribute to a 7-run comeback victory, the largest in Opening Day history.

[citation needed] In spite of Yamada's individual struggles, Yakult secured the Central League pennant for a second consecutive year.

He played primarily as the designated hitter in the leadoff spot, and hit two home runs in one game against Cuba in the second round, becoming the eighth batter in tournament history to do so.

[129] His bases-loaded double in the semifinal round against South Korea gave Japan a 5-2 lead, which they maintained and secured a spot in the final.

Following the play, the student received a large amount of criticism on the internet, and users identified his Twitter account.

[140] According to Tsuyoshi Ueda, who played with him until the 2020 season, Yamada finds success in base-stealing because of his aggressiveness and his ability to read the opposing pitcher and catcher.

[143] Yamada initially played shortstop during his tenure in Yakult's Eastern League farm team, before becoming the regular second baseman on the main roster.