A new book claims that musician Sheryl Crow watched cyclist Lance Armstrong get an illicit blood transfusion while they were dating.
And the book says Crow told Federal Investigators what she had seen when they came to question her several years later.
The New York Daily News reports that a new book from two Wall Street Journal reporters claims Crow cooperated with authorities in exchange for immunity from prosecution.
Reed Albergotti and Vanessa O'Connell are the authors of "Wheelmen: Lance Armstrong, the Tour de France and the Greatest Sports Controversy Ever."
According to an excerpt in the post, the pair write that Armstrong told Crow that doping was "simply part of the sport" and that "all cyclists were doing the same thing."
The authors claim that Armstrong believed Crow would have no reason to ever tell anyone what she saw.
Armstrong was banned from cycling for life and stripped of his seven Tour de France titles last year amid accusations that he'd been doping for years.
In January, he admitted having used performance-enhancing drugs during his career, in an interview with Oprah Winfrey.
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