Boxer Andre Berto has tested positive for a performance-enhancing substance known as norandrosterone (also known as nandrolone), jeopardizing his June 23 world welterweight title fight against Oxnard's Victor Ortiz at Staples Center.

Berto's first and second "B" urine sample have each been declared positive by the Voluntary Anti-Doping Assn.

[Update, 7:50 p.m.: Berto released a statement that read, "At the present time, I cannot explain the positive drug test, which was provided as part of a voluntary anti-doping program in which I agreed to participate.  I know that I have never used any steroids or other banned substances, and I am investigating all possible causes of the positive test with my attorney Howard Jacobs.  I have never cheated, and all of my success has come from hard work and dedication."]

Promoter Richard Schaefer said the June 23 bout will go on with Ortiz facing another opponent if Berto is not available; Schaefer expects to have Berto's situation clarified by the California State Athletic Commission by Monday.

Berto’s promoter Lou DiBella said he was still gathering details Friday. “I've always been pro-testing and said I believed in that even if one of my own would ever be involved,” DiBella said.

Ortiz defeated Berto in the 2011 fight of the year, in which both men were knocked down.

Berto has trained during the last year-plus with Victor Conte, who was sent to prison for steroid distribution and money laundering after heading the infamous BALCO operation that counted all-time home run king Barry Bonds, Olympic-champion sprinter Marion Jones and boxer Shane Mosley as clients.  

In a prepared statement, Conte said:

"I had absolutely nothing to do Andre Berto's positive drug test for nandrolone.

"Andre enrolled in the VADA drug testing program in early 2012. While using my nutritional products and protocols, Andre's blood and urine were randomly tested twice before his recent bicep injury, and all tests were negative.

"After his positive test was revealed, Andre admitted that he recently took some supplements that were not provided by me and did so without my knowledge. It is possible that one of these supplements was contaminated with trace amounts of nandrolone and caused his positive test result."


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Boxer Andre Berto tests positive for performance-enhancing drug