Testimony continued Tuesday in the federal trial of Karen Sypher, who's charged with trying to extort University of Louisville basketball coach Rick Pitino.Tuesday's witnesses include FBI Special Agent Mike Schafer, who told jurors that Sypher wasn't believable when she denied knowing who made threatening calls to Pitino.The man who made the calls, Lester Goetzinger, told jurors earlier that he did so at Sypher's request. Goetzinger told Pitino in the calls that he would go public with damaging sexual allegations about the coach involving Sypher unless he did "the right thing."Sypher is on trial in U.S. District Court on charges of extortion, lying to the FBI and retaliating against Pitino.She allegedly demanded $10 million from Pitino, along with college tuition for her children and that he pay off her mortgage.Pitino could be called to the witness stand Wednesday.