The B-sample of Olympic gold medal winner Alexander Povetkin, as expected,  has tested positive for the banned drug ostarine following the disclosure of results analyzed in a Los Angeles laboratory. The results were disclosed on Thursday from tests on samples taken by the Voluntary Anti-Doping Association (VADA).

It was originally intended that the results be disclosed on January 6, but this date was moved by the World Boxing Council (WBC) to Tuesday.

Following the disclosure in LA, Andrey Ryabinsky, head of the World of Boxing promotional company which handles Povetkin, stressed the need to conduct independent tests.

Those tests were conducted in an independent laboratory in Lausanne, Switzerland. Ryabinsky contested that, while the samples given in LA tested positive, the independent results proved otherwise.

“An American laboratory confirmed ostarine was found in Povetkin’s ‘B’ sample. The tests given in an independent laboratory in Lausanne [Switzerland] are clean,” Ryabinsky claimed in a tweet.

He added that the concentration of the banned performance enhancing drug was “minimal.”

World of Boxing later claimed that just Povetkin’s December 6 sample contained just 0.00000000001 g of ostarine and that samples given on November 15 and December 13 showed no traces of doping.

The tests relate to Povetkin' positive read for ostarine were connected to his scheduled Bermane Stiverne on December 6, 2016, for the WBC international heavyweight title in Ekaterinburg.

The WBC subsequently refused to sanction the fight. Stiverne withdrew from the contest and Povetkin instead controversially beat Johann Duhaupas by brutal sixth-round knockout.

It wasn’t the first time a Povetkin bout had been aborted at the last minute: in May 2016, a WBC world heavyweight title fight between the Russian and champion Deontay Wilder was scrapped when it emerged Povetkin had tested positive for meldonium.

However, Povetkin was cleared by WADA of doping, but ordered to undergo extra drug testing at his own expense for the next 12 months. Another failed test in that time would mean an indefinite ban from all WBC events.