Jessica Ennis-Hill’s coach Toni Minichiello wants Russian heptathlete Tatyana Chernova’s drugs ban to be re-examined by the sporting authorities.
Chernova, now 27, beat Briton Ennis-Hill to gold at the 2011 World Championships.
Now she has been given a ban and had earlier results annulled after a sample from 2009 was re-tested - but kept her world title.
“She set a personal best with the benefit of drug use,” Minichiello said.
Russian anti-doping agency punished Chernova with a two-year ban, backdated to 22 June 2013.
It also annulled her results from 15 August 2009 to 14 August 2011 - a period that ended just 16 days before she won world gold in Daegu with a personal best of 6,880 points, beating defending champion Ennis-Hill’s 6,751.
Research by the University of Oslo in October 2013 established that muscles can retain the advantages given by anabolic steroids decades after the point at which they were taken.
Minichiello wants athletics’ world governing body the IAAF and the World Anti-Doping Agency (Wada) to have a “long, hard look” at the Russian anti-doping agency’s punishment. The IAAF told BBC Sport it is awaiting a full explanation from the Russian authorities before deciding whether it needs to take any action.
“Maybe it highlights that there is a gap within the anti-doping code which allows only a two-year ban from the initial test and then another ban from the date of the re-test,” added Minichiello.
“It should probably all run seamlessly and athletes should be banned for the whole time. Otherwise Chernova’s ban really looks quite ineffective.”
Chernova’s backdated ban is due to expire on 21 June, and with the qualification period for the 2015 World Championships in Beijing running until 10 August, she could compete both there and at the 2016 Rio Olympics.
“Wada needs to look at its code and penalties to show there is potentially a loophole that needs to be closed, added Minichiello.