Nelson was a three sport athlete at Anoka High School earning letters in football, basketball and baseball. As a senior, Nelson was selected as captain, team MVP and to the all-state team in football. Nelson then went on to college at North Dakota State University and graduated from NDSU in 1974 after being named a two-time All-American, team captain and MVP in football.
He was selected by the Patriots in the 2nd round of the 1974 NFL Draft and missed only three games during his 14-year NFL career in which he was named team MVP twice. He was selected to the Pro Bowl three times in 1980, 1984, and 1985 and his #57 jersey was retired by the Patriots. He is credited with helping the Patriots reach Super Bowl XX versus the Chicago Bears.
After his football retirement, Nelson was the athletic director and head coach at Curry College from 1998 to 2006 (football coach through 2005 season). He currently works as a business development executive for Lighthouse Computer Services, Inc., a Lincoln, RI-based technology company. In September, 2011, Nelson was named to the inaugural class of the Anoka High School Hall of Fame.
Nelson and his wife Angela reside in Middleboro, Massachusetts. He is the father of five daughters; Cameron, Casey, Caitlin, Kelli and Grace.