The Biggest Loser: Anna Kournikova Out

Although the former tennis pro "was not fired," the reality show "wasn't the right fit for her," a source tells PEOPLE

Anna Kournikova

Anna Kournikova

Biggest Loser: Battle of the Ages!!!!

Anna Kournikova Explains her Biggest Loser Exit with “TV Isn't for Me”

Anna Kournikova Biggest Loser 052311 12.JPG Orig Pix Taken 2005 in Florida MIAMI BEACH, FL - MAY 23: (Radar) It looks like 'The Biggest Loser' might have found another new trainer. According

Mark your calendar: Season 12 of The Biggest Loser premieres Sept 20!

Anna Kournikova on The Biggest Loser

Anna Kournikova

Anna Kournikova Leaving The Biggest Loser