It was his parents who pushed him into golfing.
Morikawa shared to Golf Digest that his family often traveled to Hawaii, where his fraternal grandparents still live.
When Morikawa was 5, his parents convinced the organizers of a junior golf camp at Scholl Canyon, a 3,039-yard, par-60 track, to let him participate even though he was too young.
There, an instructor named Rick Sessinghaus worked.
Sessinghaus only trained the better players, and Morikawa slowly got interested in the game and progressed, and when he was eight years old, he finally got the chance to be coached by Sessinghaus.
So after I went through the camp, my parents could see I was getting better. So they approached Rick to see if he would coach me, and by the time I was 8, we had started this relationship.
Fortunately, Sessinghaus agreed, and by the time Morikawa was ten years old, he quit playing other sports.
Under Sessinghaus' guidance, Morikawa progressed by leaps and bounds during the next few years, until the coach was convinced that Morikawa had something special.
They spent years perfecting Morikawa's golf swing, and their relationship continues to this day.
