New York Yankees third baseman Alex Rodriguez presented new details Tuesday about his performance-enhancing drug use, saying his cousin injected him with an over-the-counter drug to gain a “dramatic energy boost.”

The baseball superstar held the press conference 10 days after Sports Illustrated reported that he tested positive for steroid use in 2003 while playing with the Texas Rangers.

In an interview last week, A-Rod told ESPN’s Peter Gammons that he used banned substances from 2001 to 2003.

He said: “Back then it was a different culture. It was very loose. I was young. I was stupid. I was naive, and I wanted to prove to everyone that, you know, I was worth $252 million.”

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