Now competing as a senior, Arakel Mirzoyan lifted a total of 336 kg at the 2009 European Weightlifting Championships in Bucharest to become the European Champion. In the same year, he went to the 2009 World Weightlifting Championships in Goyang, where he lifted a total weight of 334 kg and won the silver medal, behind the reigning Olympic Champion Liao Hui. Arakel later claimed a hand injury prevented him from winning gold. In 2010, Mirzoyan changed his weight class and began performing in the weight category of 77 kg. He had to miss a number of championships in order to adjust to this new weight. At the 2011 World Championships in France, he took 10th place with a total weight of 338 kg. He returned to 69 kg sometime afterward.