 World champion in 2014, she competed for Ukraine at the 2008, 2012 and 2016 Summer Olympics.At the 2008 Summer Olympics, she lost to Randi Miller in her first match.Tkach competed in the freestyle 63 kg event at the 2012 Summer Olympics; she defeated Yelena Shalygina in the quarterfinals and Marianna Sastin in the 1/8 finals before being eliminated by Lubov Volosova in the quarterfinals.