Carlson played defensive end at Milford Academy as an underage academic scholarship student on a largely post-graduate teams, then tight end at Wesleyan University from 1968 to 1972 (where he was a contemporary of Bill Belichick). After moving to the UK in 1977, Carlson worked as a sports editor for the television news agency UPITN before joining ABC Sports as their director of programming in Europe. Later he became Vice-President of European operations for Major League Baseball before beginning his freelance career. In 1991, he teamed up with Nick Halling to cover Major League Baseball for satellite station Screensport, a partnership which continued with the World League of American Football, and during the early years of the league's successor, NFL Europe, on Sky Sports.