Knopf Doubleday is facing a defamation case, as part of a wider federal perjury investigation of baseball star Roger Clemens, ESPN reported.
Former gym owner Kelly Blair has filed a suit against the publisher over allegations made in the book American Icon: The Fall of Roger Clemens and the Rise of Steroids in America's Pastime.
Houston-based attorney Jason Gibson, was reported to have said: "There are allegations in the book about Kelly Blair that are just completely not true."
He added: "There are a number of statements of fact that were made that are false. The only defence to allegations of defamation are that it was true. In this case, it is not true."