Jurors in the perjury trial of Roger Clemens got their first up-close look Thursday at the needles, empty steroid vials and bloody cotton balls that federal prosecutors say were used to inject the pitching legend who is accused of lying to Congress when he denied using performance-enhancing drugs.

Sitting ramrod-straight in the witness chair and directly addressing jurors, government investigator Jeff Novitsky testified Wednesday that he recovered the items from Brian McNamee, Clemens’s former strength coach.

Novitsky, a special agent for the Food and Drug Administration, led the doping investigation of cyclist Lance Armstrong and of the Bay Area Laboratory Cooperative doping lab.

Evidence in the Roger Clemens perjury trial. (U.S. Attorney's office/Courtesy photo)

Federal prosecutors have said that the medical waste contained Clemens’s DNA and traces of performance-enhancing drugs. But the defense team has said it will show that McNamee could have tampered with the evidence.

McNamee, who is expected to testify early next week, is considered a critical witness for the government. He has testified that he injected Clemens with steroids and human growth hormone on several occasions.

The defense team is expected to rip into McNamee’s checkered past.

During cross-examination, which will continue Thursday afternoon, defense lawyer Rusty Hardin tried get Novitzky to establish the relationship between McNamee and Kirk Radomski, who was allegedly involved in distributing steroids to Major League Baseball and became a cooperating source for the government.

After getting a boost Wednesday from the testimony of Andy Pettitte, Clemens’s former teammate and friend, the day started on a somewhat messy note for Hardin. He asked Judge Reggie Walton’s indulgence to appear in court without his suit coat. The light gray jacket was wet, he said, from spilled coffee.

“It’s not causal day today. It’s that he had an accident with his coffee,” Walton explained to jurors, prompting chuckles in the courtroom.

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