TAMPA, Fla. (AP) -- Bud Selig says Alex Rodriguez has "shamed the game," though the baseball commissioner indicated no plans to punish the three-time AL MVP. "I am saddened by the revelations," Selig said in a statement issued Thursday, four days after Rodriguez admitted he used unspecified drugs from 2001-03 while playing for the Texas Rangers. "What Alex did was wrong, and he will have to live with the damage he has done to his name and reputation."

Players and owners didn't agree to a joint drug program until August 2002, and testing with punishment didn't start until 2004.

"It is important to remember that these recent revelations relate to pre-program activity," Selig said.

"Under our current drug program, if you are caught using steroids and/or amphetamines, you will be punished. Since 2005, every player who has tested positive for steroids has been suspended for as much as 50 games."

Rodriguez's admission came two days after Sports Illustrated reported on its Web site that he was among 104 names on a list of players who tested positive for steroids in 2003, when testing was intended to determine the extent of steroid use in baseball. The results weren't subject to discipline and were supposed to remain anonymous, but were seized by the government in 2004 and remain under seal.

"When I arrived in Texas in 2001, I felt an enormous amount of pressure. I felt like I had all the weight of the world on top of me and I needed to perform, and perform at a high level every day," Rodriguez said in an ESPN interview.

Though Rodriguez said he experimented with a number of substances, he has not provided details.

"It was such a loosey-goosey era. I'm guilty for a lot of things. I'm guilty for being negligent, naive, not asking all the right questions," Rodriguez told ESPN. "And to be quite honest, I don't know exactly what substance I was guilty of using."

Much of Selig's statement Thursday was a recitation of his efforts to get a drug agreement with the union and then toughen it. With baseball officials under pressure from Congress, negotiators from management and the union strengthened the program in January 2005, November 2005 and April 2008, toughening the penalties and tightening the rules.

In 2008, there were three major-league violations and 69 minor-league violations. This year, there have been two major-league and two minor-league violations so far.

"We are fully committed to ridding our game of steroids and other performance-enhancing substances. These drugs and those who use them and facilitate their use threaten the integrity of our sport," Selig said. "... But we will not rest or relax our efforts until the use of these illegal drugs are gone from baseball."

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