Abelyan started boxing at the age of 12, and began training with the legendary Olympic Bronze Medalist David Torosyan. He started to box professionally in 1998. Abelyan had once defeated Orlando Salido, who would later be ranked the number one featherweight in the world. William was an WBONABO Featherweight Champion and was a WBO #1 ranked contender. He was named fighter of the year in 2005. Abelyan challenged Scott Harrison for the WBO Featherweight title, but lost. William is now retired from the sport of boxing.