Shohei Ohtani’s father, Toru, played company baseball for Mitsubishi Heavy Industries Yokohama until the age of twenty-five.
Afterward, he joined Kanto Auto Works, part of the Toyota Group, and returned to their hometown in Iwate.

With his background in company baseball, Ohtani’s father served as manager of the Mizusawa Little League and later as a coach for the Ichinoseki Little Senior team.
Despite their relationship, he never gave his son special treatment.

Ohtani himself understood this clearly.
If another player had the same ability as the coach’s son, that player — not the son — should be the one on the field.

Because of that, Ohtani made up his mind at a very young age.
If he was going to earn a spot in games as the coach’s son, he needed to be overwhelmingly better — good enough that everyone on the team would accept it without question.

With that resolve, he practiced far more than his teammates and steadily built his ability.

Eventually, he became capable of performances such as striking out seventeen of the eighteen outs in a single game.
What drove him was not simply the desire to meet his father’s expectations, but the wish to be a player his teammates could truly trust.

Source

This quote comes from a Japanese book published in Japan and is not currently available in English.

Opening a Path, Crossing the Ocean: The True Story of Shohei Ohtani, p.89