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New York Yankees pitcher Andy Pettitte was called to the stand to testify in Roger Clemens’s perjury trial Tuesday in the District’s federal courthouse.

Pettitte is a longtime friend and confidant of “Rocket” Clemens, an 11-time all-star accused of perjury, obstruction of Congress and making false statements.

Clemens could face 30 years in prison if convicted on all charges.

New York Yankees pitcher Andy Pettitte (Eddie Michaels/AP)

The investigation into Clemens began after the pitcher denied using steroids or human growth hormone in 2008 testimony before a House committee following a 2007 report by former senator George Mitchell that identified Clemens and dozens of other players as having taken banned substances.

This is Clemens’s second trial on these charges. Pettitte played a key role the first time around, when U.S. District Judge Reggie B. Walton declared a mistrial in July after the government showed a video clip that included barred evidence.

Prosecutors led by Steven Durham and Daniel Butler played a videotaped segment of congressional testimony that referenced Pettitte’s wife.

Pettitte, who recently came out of retirement to rejoin the Yankees and was also named in Mitchell’s report, told congressional investigators Clemens confided in him about taking a performance-enhancing substance. He said he shared the conversation with his wife.

Laurie Pettitte gave Congress an affidavit backing her husband’s claims, and Walton ruled before the first trial that prosecutors could not raise her statements before the jury.

While Walton said he was troubled by the government’s misstep, he ruled that a second trial would not violate Clemens’s constitutional protection against double jeopardy, which ensures defendants are not subjected to endless prosecutions.

This item has been updated.

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