Serena Williams, the world's reigning No. 1 women's singles player, expressed her amazement at the news while graciously praising Sharapova for taking full responsibility for her actions, the New York Times reports.

Sharapova admitted to failing a drug test via her use of a formally legal substance and claims she did not know that the substance was forbidden.

After the Al Jazeera documentary, The Dark Side: The Secret World of Sports Doping, aired on Saturday implicating Peyton Manning as an HGH user, he's already shot down the allegations.