Hammink sat out the 2014–15 season due to National Collegiate Athletic Association (NCAA) transfer eligibility rules, then joined the Crusaders for the 2015–16 campaign. In his first season, Hammink teamed with Alec Peters and Vashil Fernandez to lead the team to the finals of the 2016 National Invitation Tournament. He averaged 8.9 points and 3.1 rebounds per game in the season. In his senior season, Hammink and Peters led Valparaiso to a share of the Horizon League regular-season championship. Hammink averaged 15.1 points per game and was named second-team All-Horizon League.
