(LOS ANGELES) -- Tennis star Anna Kournikova is leaving NBC's The Biggest Loser after just one season as a trainer, according to The Hollywood Reporter.
Kournikova worked on season 12 of the reality weight loss series, but after conflicts with staffers and contestants she decided to exit. A source on the show told The Hollywood Reporter that Kournikova was "a nightmare."
Meanwhile, Kournikova said in a statement, "I enjoyed my time on the Biggest Loser ranch. Although I will not be returning as a full time trainer on season 13, I will always be a part of The Biggest Loser family and my commitment to bettering lives through health and fitness will continue..."
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