Sheryl Crow and Lance Armstrong celebrated the 2004 Tour de France win. (Franck Prevel / AP)

What exactly Sheryl Crow knew about Lance Armstrong and doping has long been the subject of speculation.

The singer and the cyclist dated and were ever-so-briefly engaged back in the days when Armstrong was winning Tours de France and, as he admitted to Oprah Winfrey last January, doping. Now, according to the New York Daily News, a new book reports that she watched Armstrong receive a blood transfusion in 2005 and later sang to federal investigators about what she’d seen.

“Rather than try to hide the transfusion from her, Armstrong was completely open about it,” Wall Street Journal reporters Reed Albergotti and Vanessa O’Connell  report in “Wheelmen: Lance Armstrong, the Tour de France and the Greatest Sports Conspiracy Ever,” due out next week. “He trusted that Crow would have no desire to tell the press or anyone else about the team’s doping program. He explained that it was simply part of the sport — that all cyclists were doing the same thing.”

The couple broke up in 2005 and Crow, according to the Daily News, spoke with a Food and Drug Administration investigator in 2011 in exchange for a proffer protecting her from prosecution. Crow’s representative did not comment for the Daily News.

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