Aoki was born in Yokohama, Japan, and raised in Milton, Massachusetts. He attended Milton Academy prior to enrolling at Davidson College. Aoki earned four varsity letters while starting for three seasons for the Wildcats at catcher, second base, and third base. He was a prolific hitter and still ranks among career leaders in several offensive categories. Aoki hit two grand slams in 1988, one of just six Davidson players to hit two in one season. He played one professional season for HCAW in the Netherlands in 1991.
Aoki began his coaching career as head coach at Manchester Community College in Manchester, Connecticut. After one season, he became an assistant at Ohio, where he stayed for two years and earned a master's degree. He then moved to Dartmouth for four seasons before landing his first Division I head coaching job at Ivy LeagueColumbia. In his five seasons, the Lions were 87–140, including twenty or more wins in each of Aoki's last three seasons. Columbia had not won twenty or more games in a season since 1987.
National champion Postseason invitational champion Conference regular season champion Conference regular season and conference tournament champion Division regular season champion Division regular season and conference tournament champion Conference tournament champion