In 2012 Tasarov competed in his first major international competition when he was selected for the Russian team at the Summer Paralympics in London. Tarasov entered six events, winning medals in five of them. The highlight of his Games was his gold in the 50 m freestyle – S8, where in the heats he posted a time of 25.92, a world record. In the final Tarasov beat his own world record when he finished in 25.82, beating Maurice Deelen of the Netherlands by almost half a second. Along with his gold he left London with three silver medals, 100 m freestyle S8, 100 m backstroke S8, 4 × 100 m medley relay 34pts and a bronze in the 4 × 100 m freestyle relay 34pts.