The slog that is known as the perjury trial of Roger Clemens and its series of scheduling problems may make it difficult for jurors to reach a fair verdict, the presiding federal judge said Tuesday

His comments come as the trial, entering its eighth week, has only one remaining alternate juror, down from an original four. U.S. District Judge Reggie B. Walton said he is concerned about the panel feeling rushed once they begin deliberating the baseball legend’s fate, possibly as early as next week.

In the six weeks since testimony began, two jurors have been dismissed for sleeping on the job and another excused after her mother died.  Walton told lawyers Tuesday that one of the remaining 13 jurors plans to travel to Germany on June 19 to attend a six-month program. The judge also is worried that another juror may be dozing in court.

View Photo Gallery: The trial of Roger Clemens.

Walton noted that jury deliberations in the trial of former senator John Edwards lasted eight or nine days.

"If that happens here we’re in trouble,” said Walton, whose own travel plans mean the trial will recess for two days next week.

As testimony continued Tuesday, one of Clemens’s former Red Sox teammates called by the defense team testified that he watched the pitching legend get injected with liquid vitamin B-12 by an athletic trainer in the clubhouse at Fenway Park.

“It was commonplace for trainers to give shots back then,” former right-handed pitcher Mike Boddicker testified.

Clemens is charged with committing perjury, making false statements and obstructing Congress in 2008 when he denied using performance-enhancing drugs during a House hearing. The hearing followed a report by former Sen. George Mitchell about the abuse of steroids in big league baseball.

Prosecutors allege that Clemens obstructed Congress when he told House investigators in a deposition that he was routinely injected with the vitamin B-12 by his strength coach and chief accuser, Brian McNamee. Clemens also told investigators that syringes of the vitamin were “lined up ready to go” after games.

The government’s witnesses, including New York Yankees General Manager Brian Cashman, have testified that McNamee and other strength coaches would not have had access to or the authority to give such injections. And they testified that they never saw pre-loaded needles in team clubhouses.

Defense attorney Rusty Hardin questioned Boddicker to suggest that the vitamin injections were part of the culture of big league baseball in the late 1980s and early 1990s.

On cross-examination, assistant U.S. attorney Steve Durham suggested that teammates were like family, conditioned to protect each other’s reputations and secrets. Boddicker agreed: “What happens in the clubhouse stays in the clubhouse.”

 But Hardin quickly tried to undo any impression that Clemens was engaged in untoward activity when he asked Boddicker if there was anything the ballplayer did that he asked his teammates to keep secret. After batting practice, Clemens left the ballpark in his uniform to visit sick children at a local hospital, Boddicker told jurors.

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