A returning letterwinner for the Gators, Mark Castillo played in nine singles matches as a rookie. He played at fourth, fifth and sixth singles for Sage last season. He also played in five matches in doubles competition for the Gators.

A graduate of Randolph (MA) High School, he participated in both basketball and track scholastically. As a member of the 2009-2010 track team, he helped the Blue Devil program to the conference championship as a senior. He started his collegiate days as a student at Wentworth Institute of Technology before arriving at Sage and is a physical education major at Sage. He is the son of Edgardo and Ophelia Castillo.