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John Diffley is in his 12th year as Senior Associate Athletic Director at St. John’s University where he manages daily operations for the Red Storm’s 17 varsity sport programs. Diffley oversees facilities and operations, event management, sports medicine, sports performance, equipment operations, and is a key liaison for head coaches and with university leadership. Diffley’s responsibilities include personnel management, oversight of capital projects, planning and fundraising. In addition, he is involved in maintaining and developing strategic partnerships. Diffley works closely with IMG College, corporate sponsors, and manages an exclusive all sports partnership with Under Armour. In his time at St. John’s, Diffley has been involved in significant facility upgrades including the multi-phase renovation to Carnesecca Arena, expansion of the sports medicine treatment area, renovation of sports performance training center, creation of an indoor golf practice facility, and installation of a state-of-the-art turf field and track at DaSilva Memorial Field. In addition, Diffley is the sports administrator for men’s lacrosse, men's soccer, women's soccer, fencing, golf, cross country, and track and field. Diffley has represented St. John’s on numerous committees during his tenure in Queens. He is a member of the BIG EAST Presidents’ Award Selection Committee, chaired the NCAA Division I Men's Soccer Committee for two years, and has also served as the Chair of the BIG EAST Men's Soccer Committee, NSCAA Board of Governance Task Force, St. John’s Campus Climate Committee, CSIRT Committee, Vice President’s Round Table, St. John’s University Facilities Planning Group, and the Strategic Priorities Review Team. Diffley was the Tournament Director of the 2012 NCAA Women’s Basketball Championships First & Second Rounds, and the Assistant Tournament Director of the 2014 NCAA Men’s Basketball Regional at Madison Square Garden. He is currently serving as the Tournament Manager for the 2017 NCAA Men’s Basketball Regional at MSG. Diffley has been honored for his dedicated service with the Outstanding Achievement Award at St. John’s University.
Prior to becoming an administrator, Diffley was head coach at Dominican College for two years and was a key member of St. John’s nationally-recognized men's soccer program as an assistant coach for four years. In that span, the Red Storm reached the NCAA Tournament Round of 16 for four-consecutive seasons, and won two BIG EAST titles.Diffley earned his master’s of business administration at St. John’s University, he spent three years working in the financial services sector for State Street Capital, a company that leads the industry in providing hedge fund infrastructure.
Diffley played professional soccer both in Europe and the United States and was the 27th player chosen in the inaugural Major League Soccer draft. Diffley also competed for the United States National Team, and was an alternate member of the 1988 United States Olympic Team. For his on-field achievements, Diffley has been inducted into the Albertus Magnus Hall of Fame, American University Hall of Fame, and the Rockland County Sports Hall of Fame.Diffley resides in Floral Park, N.Y., with his wife, Marcia, and four daughters, Jacqueline, Nicole, Kate and Jessica.