Brian McNamee asked a federal judge to throw out Roger Clemens' defamation suit and to disqualify the pitcher's lead attorney.

McNamee's lawyers filed motions Tuesday in U.S. District Court in Houston, where the case was moved after Clemens filed it in Texas state court. They said that because McNamee made statements to baseball investigator George Mitchell as part of an agreement with federal prosecutors, anything McNamee said to Mitchell was covered by "absolute immunity."

An initial conference is scheduled for April 9, and the case has been assigned to U.S. District Judge Keith P. Ellison, a former law clerk for Supreme Court Justice Harry Blackmun. Ellison was nominated for the bench by former President Clinton.

Clemens claims he was defamed when McNamee, his former personal trainer, said the pitcher used steroids and human growth hormone from 1998-2001

"Rather than acknowledging the truth of Mr. McNamee's allegations, Mr. Clemens has chosen to wage a public-relations battle against Mr. McNamee in the media and the Halls of Congress," the motion stated.