Born in Fergana, Uzbekistan, Darkin has been a regular member of the Russian World Team Cup squad, finishing runner-up in 1996. He was Russian individual champion in 2000 and 2002.
After riding in the UK for Eastbourne Eagles in 2001, he joined Coventry Bees in the middle of the 2004 season, riding in fifteen matches in the Elite League and scoring 111 points at an average of 6.68. He also rode for Arena Essex in 2005 and Poole Pirates in 2007. In September 2005 he suffered serious head injuries in a crash at Togliatti in the European Club Team Champions Cup, but was able to return to racing the following year.
He rides for KMZ Lublin in the Polish league, Togliatti in Russia, and signed for Leicester Lions for the 2011 British season, leaving mid-season. He subsequently rode for Swindon Robins in the Elite League.