In Cassidy’s freshman campaign he pitched 9 innings in relief, striking out 4 in 6 appearances.
Prior to UMass, Cassidy played his high school baseball at Cushing Academy in Ashburnham, Mass., where he was a Central New England Prep all-star as a junior and senior. He led his team to a 23-3 record as well as a Central New England Prep Championship his junior year. He was recruited by the New York Yankees and Chicago White Sox before choosing to play collegiate baseball.