Updated

By Ian Simpson

WASHINGTON (Reuters) - New York Yankees' pitcher Andy Pettitte testified on Tuesday that former teammate and close friend Roger Clemens told him he had taken human growth hormone but, years later, said he had been referring to his wife's use of the drug.

Pettitte is one of the most anticipated witnesses in the trial of Clemens, charged with lying to Congress about his alleged use of performance-enhancing drugs. They became teammates and longtime friends who worked with the same personal trainer, Brian McNamee, another important figure in the case.

Clemens had spoken to him about drug use while they were working out in Houston during the off-season in 1999 or 2000 under McNamee's direction, Pettitte told jurors at U.S. District Court.

"Clemens mentioned that he had taken human growth hormone, it could help with recovery, and that's all I really remember about the conversation," he testified.

Under questioning by prosecutor Steven Durham, Pettitte said he then approached McNamee about using human growth hormone, probably the same day.

Pettitte, 39, said he used the hormone in 2002 and 2004 to recover from injuries. Then in 2005, when he and Clemens were in Florida for spring training with the Houston Astros, he again spoke again with Clemens about his alleged use of human growth hormone, saying he had heard about upcoming congressional hearings on drug use in baseball and was concerned that media attention could focus on him.

'MY WIFE DEBBIE USED IT'

"He just said, 'What are you talking about?' And I said, 'Well, didn't you tell me that you used it?' And he said, 'No, I didn't tell you that, I told you my wife Debbie used it,'" Pettitte said.

He added, "That was really it. I just walked out."

He said he was unsure of its effectiveness and regretted taking it because of the furor that has arisen. "If I never would have done it, I wouldn't be here today," said Pettitte, who was dressed in a light gray suit and white shirt.

Pettitte said he had never seen any sign that Clemens, one of the most feared pitchers in baseball during his 24-year career, had ever used performance-enhancing drugs.

Pettitte, questioned by defense attorney Mike Attanasio, said Clemens had a great work ethic, nearly perfect technique and a repertoire of pitches that was unmatched.

"That's what makes you great, being able to repeat it (a pitch) over and over," said Pettitte, who replied to questions with short sentences and one-word answers and did not look at Clemens.

Clemens, 49, a seven-time winner of the Cy Young award, baseball's highest annual honor for a pitcher, watched Pettitte without emotion, sitting forward in his seat at the defense table.

Pettitte had testified to the House of Representatives' Committee on Oversight and Government Reform in 2008 that Clemens told him in 1999 or 2000 and then again in 2005 that he had used human growth hormone.

Clemens told the panel that while Pettitte was a close friend, he "misremembers" the conversations.

Pettitte and Clemens worked out together during the off season and often acknowledged their close relationship.

ORDER OF WITNESSES

Pettitte, the second witness in the case, was something of a surprise since prosecutors have not disclosed the order of appearance of their witnesses.

Clemens is being tried for a second time on federal charges of lying to the Oversight Committee about whether he used anabolic steroids and human growth hormone.

The panel was investigating drug use in Major League baseball. Clemens is among the biggest baseball names linked to alleged drug use.

The trial is expected to last about six weeks.

Clemens first went on trial last July, but Walton declared a mistrial because prosecutors showed jurors a video clip that included material he had banned from the case unless it was raised by Clemens' defense team.

Pettitte has come out of retirement to bolster the Yankees' pitching staff and is playing his way back into shape with a Yankee farm club.

(Editing by Paul Thomasch and Philip Barbara)