Multiple sources subsequently revealed an astonishing story of identity theft and fraud.
It begins in 2014 when Russia invaded Crimea, then part of Ukraine, and home to Kseniya Savina, a promising track athlete.
Savina, who grew up in Simferopol, took on Russian nationality following Crimea's annexation and began to compete for her adopted country.
But disaster struck a year later when Russia was banned from international competition owing to revelations of massive state-backed doping.
At 26, Savina's career appeared to be finished, until she took matters into her own hands.
Under an assumed identity and another nationality Savina competed abroad frequently over the ensuing three years.
She borrowed the name and nationality of childhood friend Galina Syshko, a one-time 800-metre runner who also happened to look like her, though two years younger.
Syshko might have had the looks, but she never had Savina's talent, according to the Russian magazine Match which first revealed the fraud.
Syshko recorded a modest 2min 17sec over 800 metres as a young runner, then disappeared without trace from athletics for five years, before emerging in July 2016 with an impressive time of 2min 04sec.
That improvement coincides with the identity switch which saw Savina competing in events in Belgium, France and elsewhere under her assumed name.
The real Syshko stayed in Simferopol, working as a sports coach at a local school, where Savina's husband Alexei Savin also worked. Contacted by AFP, she declined to comment. Savina and her spouse were unavailable to comment.
"There is a danger that athletes begin to look for alternative ways to compete internationally" since the ban, Russian Athletics Federation sports director Andrei Kruporushnikov told AFP.
"Savina and her coach have already been summoned to explain the allegations of her competing with false documents. She has denied it," he added.
- Personal best -
Even as she competed abroad as Galina Syshko, Savina continued to run in Russia under her own name.
In the 2017 Russian championships she registered 1min 59.97sec, her personal best.
In between domestic events she travelled around Europe with her husband, who acted as her agent.
Frenchman Jean-Paul Jacob, organiser of an indoor athletics meet in Eaubonne, north of Paris, in 2017, said he received an e-mail from a runner named Syshko.
"I thought she wrote the e-mail herself to compete. I liked it and I saw her time -- 2:04 -- and invited her on that basis," he said.
Resources for thorough checking of identities is beyond the scope of many small athletics organisations.
"International athletes all have a number and we would like our database to be linked to international ones but it is not possible," said François Maingain, a coordinator with the Brussels Grand Prix where Savina has appeared.
Internationally Savina maintained a low profile, but risked a return to Ninove in Belgium in 2016 and 2017 after competing there under her real identity in 2014.
Now that she has been unmasked, other problems are piling up. Savina was handed a provisional suspension in June 2018 after testing positive for the banned blood-booster EPO. She has also been targeted for allegedly tampering with part of a doping control.
Russian and Ukrainian athletics federation officials are investigating her case, but in the meantime Savina has announced her retirement from the sport ahead of her 30th birthday.