TAMPA, Fla. (AP) - Alex Rodriguez has offered new details about his performance-enhancing drug use, saying his cousin injected him with an over-the-counter substance to gain an energy boost.

The New York Yankees star says using the banned drug that he says he obtained from the Dominican Republic was a "stupid mistake."

Rodriguez met the media Tuesday, 10 days after Sports Illustrated reported that he tested positive in 2003.

Rodriguez started his news conference by reading from a prepared statement. At the end, he paused for 37 seconds, turned to his teammates and said "thank you." Sitting in the front row were Derek Jeter, Andy Pettitte, Mariano Rivera and Jorge Posada.

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