[3] He signed a five-year contract with the Capitals and would become the second Black Canadian to play in the NHL, following Willie O'Ree.

[7] During his career in the American Hockey League, Marson played for the Baltimore Clippers, Springfield Indians, Hershey Bears, Philadelphia Firebirds, and Binghamton Dusters.

[citation needed] At age 17, while playing junior hockey in Sudbury, Ontario, Canada, he suffered the loss of his mother who died unexpectedly of a brain aneurysm.

Marson became a seventh degree black belt in the Japanese style of Shotokan, attaining the status of Master-Shihan.

[12] Marson has developed an off-ice martial arts training program for hockey players designed to improve timing, focus and confidence.