Anna Kournikova Leaving The Biggest Loser After One Season

Two months after making her debut as a trainer on The Biggest Loser, tennis pro Anna Kournikova is stepping down from the popular NBC series.

Kournikova, 30, confirmed in a statement to Us Weekly Monday that she will not be returning for the show's 13th season.

"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," Kournikova told Us.

Replacing Jillian Michaels for season 12, Kournikova reportedly made waves behind the scenes. A show source cited by The Hollywood Reporter (which first broke the news of her exit) called the trainer "a nightmare" and argued that she did not sympathize with her overweight clientele.

"It wasn't the right fit for her," a Biggest Loser insider confirmed to Us. "[Her exit] was a mutual decision."