Roger Clemens' lawyer opened his defense of the former pitching star by telling jurors that evidence purportedly showing Clemens used steroids was manipulated by his former strength coach, Brian McNamee.

Prosecutors played audio and video clips Monday of Roger Clemens making a host of statements to congressional investigators that the government will try to establish were lies. "I haven't done steroids or growth hormone," Clemens says on his 2008 congressional deposition."

Federal agent Jeff Novitzky returns for a third day of testimony Monday in the Roger Clemens perjury trial, while behind the scenes Clemens' lawyers sought to strike the testimony of former teammate Andy Pettitte.

The judge in the Roger Clemens perjury case ruled Thursday that the government can call former major leaguer David Segui and another man to testify about conversations they had with Clemens's chief accuser, Brian McNamee.

Brian McNamee said that at the time of Roger Clemens's request for help in 1998 that he had no physical evidence that Clemens had been a steroids user but he referenced a conversation he overheard the pitcher have with another player, Jose Canseco.