An emotional Alysia Montano branded her career "a farce" and the IAAF a "corrupt institution" after missing out on a place in the United States' Olympic squad.
The 800-metre runner missed out on a place at Rio 2016 after a collision with Brenda Martinez resulted in Montano finishing last at the USA Olympic trials in Eugene on Monday.
Montano, one of the favourites for the race, was in tears as she got back to her feet and made her way to the finish line.
The 30-year-old finished fifth at London 2012, but Russian duo Mariya Savinova and Ekaterina Poistogova have since been linked to doping by an independent report commissioned by the World Anti-Doping Agency.
It leaves a bitter taste for the Montano, who was also denied medals at the 2011 and 2013 World Championships by Savinova's presence in the top three.
"I'm missing three medals in like eight years of my life as a professional runner," said Montano.
"My entire professional career has been a farce, basically."
However, Montano levelled part of the blame at the IAAF, adding: "Now everyone is talking about the Russians not running in the Olympics but they are missing the whole point that the IAAF is a corrupt institution which is still running the game for us professional athletes.
"Trying not to take that anger with me to today and still try to be in the sport, knowing that who's been running the show have been using us all along. That's why it was an emotional struggle for me.
"And I made it all the way to the final, with all that emotional baggage."