Started playing rugby for Duluth Rugby Football Club while attending the University of Minnesota Duluth and earning a Bachelors Degree in Secondary Education. In 2010, was recruited to play for the Chicago Griffins in Super league and Division 1 sides until 2013 when he moved to Minneapolis to play for Metropolis Rugby Club on their Division 1 side. He also had a stint in Durban, South Aftica in the summer of 2011 playing for the Northwoods Crudsaders in the Durban Premier Club League. Selected to the Eagles Selects in 2012 & 2013 for the American Rugby Championships and earned his first cap with the Eagles coming on in a match against Romania on November 24th, 2012.
Graham has earned 4 caps in total and was a starter against the Maori All Blacks in November 2013. In 2014, joined James Bay in Victoria, BC Canada and won the BC Premier Title in May 2014. Harriman currently plays for James Bay Athletic Association in Canada's BC Premier League.