A doping test saga that dragged on for more than two years is finally over for Olympic swimming champion Kylie Palmer.
But a frustrated Palmer admits she may never know how it all began.
Palmer can set her sights on the 2016 Rio Olympics after the World Anti Doping Authority opted not to appeal her reprimand from swimming's governing body FINA.
While relieved, Palmer said it would haunt her how she could have tested positive to low levels of a banned masking agent in July 2013.
"I don't think I will ever know how this arose, which is frustrating," she said.
"But I remain very supportive of the efforts of the swimming authorities to do everything they can to maintain a clean sport."
Palmer tested positive to "minute" levels of a banned diuretic at the 2013 world championships but was not notified until April this year.
Despite denying taking any performance-enhancing drugs, the 25-year-old Palmer voluntarily accepted a provisional suspension - ruling her out of July's world championships in Russia - while FINA investigated the matter.
FINA announced in September that Palmer would only be issued with a reprimand and a warning, although that decision was still the subject of a WADA appeal.
Palmer - a 2008 Beijing 4x200m relay gold medallist - welcomed WADA's decision on Tuesday not to appeal FINA's call.
"I am so relieved this is now over and I can try to put it all behind me," she said.
"It really has been very difficult to deal with the uncertainty of the situation."
Palmer can now prepare for the Australian Olympic team qualifiers in Adelaide in April without the issue hanging over her, having almost walked away from the sport during the ordeal.
"There have been some testing times, particularly when I was forced to miss the world championships ...but I have had great support throughout from lots of people," Palmer said.
FINA confirmed that it had initially resolved not to continue with Palmer's case after she tested positive in 2013 but was pressed into action by WADA.
During the Palmer drama, Australian head coach Jacco Verhaeren asked for more transparency from FINA's doping panel.
Palmer's lawyer Stephen Meade also hoped that was the case after efforts to find out the cause of the 2013 positive test were made near impossible due to the late notification.
"The decision affirms the importance of timely notification to the athlete of a positive test," Meade said.
"We know the WADA Code imposes strict obligations on athletes, and rightly so, given the importance of integrity to all sports.
"But this case recognises that sports administrators also carry the burden of strict compliance with the code so that athletes can investigate and rely on the defences available under the code in very limited circumstances."
