updated 11:38 a.m. ET Feb. 12, 2009

Baseball commissioner Bud Selig on Wednesday left open the possibility of punishing New York Yankees third baseman Alex Rodriguez for using performance-enhancing drugs. Selig also said he might consider amending the record book to acknowledge steroids use by players.

Selig said he would look into the possibility of reinstating Hank Aaron — a personal friend — as No. 1 on the all-time home run list and attach asterisks or some other note to the records of players involved in steroids use.

"Once you start tinkering, you can create more problems," Selig said, USA Today reported. "But I'm not dismissing it. I'm concerned. I'd like to get some more evidence."

Barry Bonds, who is widely suspected of using performance-enhancing drugs, is baseball's all-time home run leader with 762. Aaron has 755. Rodriguez is 12th with 553.

Selig told USA Today in a telephone interview he "would have to think about" taking action against Rodriguez, saying the player broke the law by using PEDs. Selig refused to be specific about possible penalties, and he indicated a decision would not be made quickly.

Rodriguez admitted Monday he used banned substances from 2001-03 as a member of the Texas Rangers. Two days earlier, Sports Illustrated reported Rodriguez was one of 104 major league players who failed what was supposed to be a confidential drug test in '03. MLB and the players association began a full drug testing program in 2004.

Donald Fehr, the association's executive director, told USA Today he was not expecting Selig to take any action. "I would be surprised if there was an attempt to do it," the newspaper quoted Fehr as saying. "I don't know anything about that."

The Yankees have said they would not discipline Rodriguez.

Also, Wednesday, ESPN.com reported that at least eight players among those 104 tested positive for over-the-counter supplements that weren't banned by baseball until 2005. The website cited an unidentified "highly placed Major League Baseball source."

Meantime, the chairman of the committee that determines the banned-substances list for the World Anti-Doping Agency says he still has plenty of questions for Rodriguez.

"In doping, the devil is in the details, and I think he needs to come forward with the details," Gary Wadler said.

Among the questions Wadler would like to ask:

• Did Rodriguez take steroids orally, by injection or both?
• How did he obtain the substances he used?
• Did he inject himself? Did someone else inject him?
• Was he taking dietary supplements?
• Did he share vials?
• Did he use in-season, offseason or both?
• How frequently did he use each substance?
• Did he use multiple substances at the same time?

"Those questions have to be asked and answered, and not only answered, but it has to answered in a convincing manner, not through a handler or a Word Smither," Wadler said.

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