Alex Rodriguez is making his case at Major League Baseball headquarters on Park Avenue in New York. (David Karp / AP)

Updated with Rodriguez’s denial

A cornerstone of the case Alex Rodriguez’s lawyers are making in his Major League Baseball arbitration grievance hearing is that he believes the substances he obtained from the Biogenesis clinic were legal supplements, according to the New York Daily News.

As the Daily News puts it, he contends that, if he doped, he was duped.

A three-person panel is hearing A-Rod’s appeal of the 211-game suspension that baseball officials handed down this summer. His lawyers say he believed he obtained legal supplements from clinic founder Anthony Bosch , who testified to the contrary Monday and Tuesday. Rodriguez’s lawyers are expected to cross-examine Bosch today.

The New York Yankees’ third baseman was the most severely punished of the 14 players penalized by MLB for being connected to Biogenesis. Rodriguez was suspended Aug. 5, but, because he’s a first-time offender under the drug program and the Major League Baseball Players Association filed a grievance on his behalf to to force an appeal, a suspension must be upheld by an arbitrator before it can begin. Barring a settlement, arbitrator Fredric Horowitz would issue a decision this winter.

The Daily News notes: “By claiming that he was given banned drugs when he thought he was getting legal supplements, Rodriguez is tearing a page from the playbook that guided other tainted athletes. Barry Bonds told a grand jury in 2003 that he thought the creams he got from his BALCO-affiliated trainer, Greg Anderson, were something like flaxseed oil. Roger Clemens claimed he thought the intramuscular injections he got from his trainer, Brian McNamee, were shots of vitamin B-12 and lidocaine.”

Rodriguez denied the Daily News report, saying in a statement: “We cannot provide any details of this hearing as the Chair of the Arbitration Panel
has issued order prohibiting all parties from commenting publicly on the confidential proceedings, but what is being reported is NOT true.”

A-Rod is drawing support from Hispanics Across America, a group that has been demonstrating on Park Avenue all week.

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