As a freshman, Clark played for LIU Brooklyn as a preferred walk-on but vowed to his mother, Shontay Watts, that he would eventually earn a scholarship.[6] In his only appearance, he played two minutes in a loss to Dartmouth.[5] As a sophomore, he was awarded a full scholarship and averaged 6.2 points and 4.2 rebounds per game.[2] On November 10, 2017, Clark scored a career-high 34 points in a 102–96 loss to Tulane.[7] In his junior season, he averaged 17.3 points and seven rebounds per game, earning Third Team All-Northeast Conference (NEC) honors. He led LIU Brooklyn to the 2018 NEC tournament championship, scoring 20 points in a 71–61 victory over top-seeded Wagner, and an appearance in the NCAA Tournament.[6] As a senior, Clark averaged an NEC-high 18.9 points, 6.7 rebounds and two assists per game and was named to the First Tetam All-NEC.[4] On February 8, 2020, he passed Jamal Olasewere to become the all-time leading scorer for LIU and LIU Brooklyn.[8] In his redshirt senior season at LIU, Clark averaged 19.5 points and 7.3 rebounds per game, leading the NEC in scoring and making the First Team All-NEC for a second straight year. He became the seventh player in NEC history to record at least 2,000 career points.[9]