While Perebiynis was a talented junior and a respected doubles player, she has had less success in singles on the main tour. Though she swiftly climbed up the ranks early in her career, reaching the third round at both Roland Garros and Wimbledon in 2004, her tennis career faltered when she was diagnosed with a viral infection in mid-2005. She was forced out of competition for over six months and, as a result, her ranking dropped to outside of the top 200. In October 2007, Perebiynis re-entered the top 100 after qualifying for the Kremlin Cup, jumping over 30 places to 97 in the rankings.