This 12th season of The Biggest Loser saw the departure of starring trainer Jillian Michaels, who had been with the series since its inception. Hired to replace Michaels was the household (if not unspellable) name of former professional tennis player, Anna Kournikova. Although NBC was optimistic about Kournikova's joining the series -- considering her notoriety and expertise with physical well-being -- she will not be returning to The Biggest Loser for another season.
On the series, Kournikova trains contestants alongside Bob Harper, who has also been with the show since its beginnings in 2004. For reasons not yet entirely explained, Harper will be alone once more. Kournikova stated, "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's replacement is not yet determined. The Biggest Loser airs Tuesdays at 8 p.m. ET/PT on NBC.