SAN FRANCISCO (CBS SF) — Testimony in the Barry Bonds perjury trial was postponed until at least Tuesday because one of the jurors called in sick, suffering from gallstones.

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Meantime, federal prosecutors were to trying get new evidence admitted – a secretly-recorded conversation involving Bonds’ orthopedic surgeon reportedly located over the weekend – that they claimed might abruptly turn the case in the government’s favor.

KCBS’ Doug Sovern Reports:

The trial had been scheduled to enter its third week Monday following a three-day break, with the last government witness – anti-doping expert Dr. Don Catlin – scheduled to complete his testimony.

U.S. District Judge Susan Illston sent the jury home after juror No. 9, a 60-year-old data center engineer for and father of four, called in. Illston said the juror’s note said the absence—which she said was for gallstones—would continue for “most likely the rest of the week.”

The judge considered replacing the ill juror with an alternate and continuing the trial, but at the request of both prosecution and defense — she agreed to send the jury home and wait until Tuesday to re-evaluate the situation.

Illston said her clerk would need to “explore with (the juror) what his situation is.”

The attorneys said they feared excusing the ill juror could jeopardize completion of the trial because there were only two alternates. Replacing the ill juror would leave just one remaining alternate.

There are currently eight women and four men on the jury. Both alternates are women.

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Bonds, 46, is on trial on charges of lying in 2003 to a grand jury that was investigating the sales of performance-enhancing drugs by the Bay Area Laboratory Co-Operative, or BALCO.

The former San Francisco Giants slugger is accused of lying when he told the panel he never knowingly received steroids or human growth hormone from his trainer, Greg Anderson, and never received any kind of injection from Anderson.

The trial – which had been expected to end this week – was further unsettled Monday by a series of arguments about evidence.

Prosecutors announced that their key witness, former Bonds business partner Steve Hoskins, had located a previously missing secret audiotape made a number of years ago of an alleged conversation between Hoskins and Bonds’ surgeon, Dr. Arthur Ting.

Assistant U.S. Attorney Matthew Parrella said that the tape may contradict some of Ting’s testimony and that they may need to call Hoskins or Ting or both back to the witness stand.

In testimony last week, Ting denied Hoskins’ statements that Hoskins had talked to Ting as many as 50 times about steroids and other drugs in connection with Bonds. The doctor said he had only one general conversation, not pertaining to Bonds, about steroids with Hoskins.

The contradiction of Hoskins’ important witness appeared to mark a turning point in the case.

Illston said she would consider whether the newly discovered tape should be allowed as evidence after a transcript was prepared and defense attorneys had a chance to examine it.

Defense attorneys also asked for an evidentiary hearing on whether prosecutors failed to tell them about potentially favorable evidence stemming from a 2006 meeting with Ting.

Illston declined to order such a hearing, saying prosecutors engaged in “sloppy practice,” but that she found “no need for an evidentiary hearing at this time.”

But the judge said she would allow defense attorney Cris Arguedas to file a statement under seal about another piece of evidence that the defense claims prosecutors failed to disclose.

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