Major League Baseball gave a congressional committee about 400 pages of documents on drug testing and said Commissioner Bud Selig was willing to testify at Thursday’s hearing on steroid use.

Lawyers for Jason Giambi, Frank Thomas, and Rafael Palmeiro asked the committee to withdraw subpoenas for their clients, and lawyers for players and the commissioner’s office continued to negotiate with committee staff yesterday, trying to narrow the scope of questioning.

Just three days before the hearing, it remained unclear whether Mark McGwire, Giambi, Curt Schilling, and other current and former stars would testify before the House Government Reform Committee.

Former AL MVP Jose Canseco and Schilling are the only players who have said they are willing to appear in Washington on Thursday. Selig, who initially offered a top aide as a substitute, reversed course yesterday and offered to appear.

“I am proud of the progress baseball has made on the subject of steroids and performance-enhancing drugs and look forward to sharing this information with the committee,” he said in a statement. “The players stepped up this past January for an even stricter drug policy beginning this season demonstrating that all of us in baseball are committed to reaching zero tolerance.”

Sammy Sosa, Thomas, and Palmeiro were subpoenaed last week along with Canseco, whose recent book alleged several top players used steroids. Union head Donald Fehr also was summoned along with Rob Manfred, the executive vice president in charge of labor relations, baseball executive Vice President Sandy Alderson, and San Diego General Manager Kevin Towers.

Canseco has asked for immunity in order to speak more freely. Canseco’s lawyer, Robert Saunooke, said players were unsure whether the committee had power to grant immunity from both federal and state prosecution.

In its subpoena last week, the committee asked for 11 types of documents, including current and past drug-testing agreements and policies going back to 1970, test results from 2003 and 2004, past management bargaining proposals and studies, and details of disciplinary action since 1990 related to drug use. It also asked for results of tests since given to players subject to “cause” testing.

“We gave them roughly 400 pages of documents, substantial compliance with all of the issues they identified in their subpoena relating to our policies and our aggregate numbers,” said Stan Brand, a lawyer for the commissioner’s office.

Asked what was not turned over, Brand responded: “We presented them with the gross figures, how many people were tested, and how many turned out positive and for what. We did not give anything relating to individual tests and results.”