Mexican fencer Paola Pliego has been cleared of alleged doping charges after a second test ordered by the International Fencing Federation revealed no presence of a prohibited substance. The initial test came back positive and she was banned from the Rio Olympics.

According to a report by Mexican magazine Proceso, the IFF asked for a second test to find whether Pliego had actually taken modafinil -- a stimulant used to treat narcolepsy.

Pliego was considered a medal contender for Rio after winning bronze in the team sabre competition in June at the Pan American Fencing Championships in Panama. She won bronze in the individual event in 2015.

After testing positive after the Panama competition, Pliego gave an emotional press conference on July 31 denying she taken any banned substances.

According to Mexico's National Control Laboratory -- which is under the National Physical Culture and Sports Commission (known as CONADE by its Spanish acronym) and accredited by the World Anti-Doping Agency -- Pliego's first test had detected 540 nanograms of the substance in her system.

A second test conducted by Hans Geyer, a doctor based in Cologne, Germany, came back negative for modafinil.

Geyer stated that a different method was needed to test for the substance, and WADA asked CONADE to send the original urine sample to his lab in Germany.

"I will not allow this cloud, which I want to leave behind, to end my sporting career," Pliego said in a statement released on her Twitter account. "I will pick myself up and will fight to recover all that I lost and that was unjustifiably taken from me.

"My goal now is to only win an Olympic medal for Mexico and to give the country that I love and proudly represent that joy."

The IFF notified Pliego of the result on Sept. 12 and decided to drop anti-doping sanctions against her.

Paola must wait 42 days from Sept. 12 because CONADE can appeal the findings.

Pliego said during the July press conference that she suffers from asthma and takes the supplement manganese, which, if combined with modafinil, could have been fatal.