By Aly Semigran
Updated November 14, 2011 at 08:05 PM EST
Credit: Chris Haston/NBC

First Jillian, now Anna.

The Biggest Loser will be down another trainer, as tennis star Anna Kournikova will exit the weight-loss competition series after just one season. Kournikova said in a statement regarding her decision to leave the show, “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.”

Biggest Loser executive producer Todd Lubin told EW of Kournikova’s addition back in September, “You’re going to be blown away by how sincere she is, how intense she is, how focused she is for these folks. She’s totally dedicated to the point where she’s getting Bob back into the gym. At one point she breaks down in tears, just because she’s so moved by the stories. None of it is fake.”

(Additional reporting by Kate Ward)

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