Nairus was a three-year starter on the Holy Cross men's basketball team, helping lead the team to an overall record of 69-48 (.590) over the course of his career, with the Crusaders advancing to the National Invitation Tournament in 1990. During his senior year, he led the team in both scoring (18.4 points per game) and rebounding (7.8 rebounds per game), and was named first team All-Patriot League and to the Patriot League All-Tournament team. Nairus was also a second team All-Metro Atlantic Athletic Conference selection as a junior, when he averaged 14.3 points and 5.9 rebounds per contest. He finished his career with 1,234 points and ranked as Holy Cross' 15th all-time leading scorer, in addition to ranking second in school history in career three-point field goal percentage (48.1 percent, 116 of 241). In addition to his accomplishments on the court, Nairus was a two-time Academic All-American, in addition to being named the 1991 Patriot League Scholar-Athlete of the Year and the 1991 Crusader of the Year.