Photo Credit: Jason LaVeris/FilmMagic
Kournikova, 30, was one of the trainers hired to join Bob Harper in season 12 to guide contestants after fitness guru Jillian Michaels exited the weight-loss competition in 2010. But according to the Hollywood Reporter, the leggy blond tennis pro wasn't a popular choice with either the crew or the competitors.
A source on the show called Kournikova "a nightmare" who couldn't sympathize with and often alienated the overweight contestants instead of inspiring them.
"One of the things about The Biggest Loser is that there's a difference between someone being able to train people versus training overweight people," former contestant Patrick House tells People. "Bob and Jillian are great at training obese people and pushing them to their limits and getting more and more. I think you have to adapt to that and I think that's what she struggled with."
But Kournikova's rep tells People that the show didn't ask her to leave. "Anna was 100 percent not fired from the show." Kournikova issued a statement saying:
"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."