At the 2012 Summer Olympics in London, Polyakov competed only in the 100 m breaststroke, because of a prior change in FINA's qualifying standard format. Unlike his two previous Games, he posted an Olympic selection time (formerly a B-cut) of 1:01.48 from the USA Swimming Grand Prix in Indianapolis, Indiana. Swimming in heat two, he picked up a third spot in 1:02.15, almost seven-tenths of a second (0.70) outside his entry time. Polyakov failed to advance into the semifinals, as he placed thirty-fourth overall on the first day of prelims.