NEW YORK – A Barry Bonds' urine sample that he provided as part of the anonymous testing that baseball conducted in 2003, has tested positive for performance-enhancing substances, the New York Times reported Tuesday.

Bonds had provided samples that did not test positive under Major League Baseball's drug-testing program, but those samples were retested after they were seized in a 2004 raid, the newspaper reported.

The new information could be a key factor in Bonds' perjury trial, which is slated to begin March 2.

Citing sources, the newspaper reported last week that authorities detected anabolic steroids in urine samples linked to Bonds that they gathered in their investigation.

It's unclear, the newspaper said, whether the 2003 sample and the samples seized in the 2004 raid are the same.

Baseball's home run king, Bonds testified to a federal grand jury in 2003 that he used the "cream" and the "clear" but did not know that they were performance-enhancing drugs. The urine samples could prove the existence of other steroids in his body.

During testimony, Bonds said he never took steroids. The government alleges that Bonds lied under oath.