Accompanied by his wife and a lawyer, Knoblauch did not reveal specifics of what he was asked or what he told staff members from the House Committee on Oversight and Government Reform.
Knoblauch was among more than 80 baseball players cited in former Senate majority leader George Mitchell's report on drug use in the sport. Asked whether there were questions about himself or other baseball players, Knoblauch replied, "I only know about myself."
His lawyer, Diana Marshall, said: "Everything was fine. He answered all the questions."
Knoblauch's closed-door interview was part of the committee's preparation for a Feb. 13 hearing. That public session is expected to focus on Roger Clemens' denial of allegations in the Mitchell Report made by Brian McNamee, the pitcher's former personal trainer. McNamee said he injected Clemens with performance-enhancing substances.
Knoblauch is a former teammate of Clemens' on the New York Yankees, and McNamee told Mitchell he injected Knoblauch with human growth hormone.
Knoblauch, a four-time All-Star who played for the Twins, Yankees and Royals, ended his major league career in 2002. He agreed Monday to speak to the committee after initially failing to respond to an invitation to testify.
"It's an important thing that they're doing here in Congress," Knoblauch said while walking through a marble hallway in the Rayburn House Office Building. "I want baseball to be fair and healthy, just like everybody else."
At one point, he told his 3-year-old son, Jake, to say, "Hi!" to the cameras tracking them as they headed for an exit.
"Maybe one day, when he grows up, he won't have to be worried about drugs in sports," Knoblauch said. "That's why I have him here today, to learn a very valuable lesson: If you do something in life, be prepared to talk about it openly and honestly. That's it."
Knoblauch's initial silence when invited to speak to the committee prompted lawmakers to issue a subpoena, but federal marshals were unable to track him down right away. The 1991 AL Rookie of the Year eventually did make contact, the subpoena was withdrawn, and his interview was rescheduled for Friday.
Current Yankees pitcher Andy Pettitte's pre-hearing meeting with committee lawyers is slated for Monday, followed the next day by Clemens' scheduled appearance. McNamee is to appear Thursday, and former New York Mets clubhouse employee Kirk Radomski on Feb. 12. Those appearances all were announced by the committee.
At least one unannounced interview has taken place. On Thursday, an employee of the sports agency that represents Clemens and Pettitte spoke to committee lawyers.
The agent, Jim Murray, said in a statement: "I answered all the questions they asked of me."
"Mr. Murray cooperated fully with the committee," his lawyer, Lawrence Finder, said in a telephone interview.
Murray's name was mentioned several times in a recorded conversation between Clemens and McNamee that the seven-time Cy Young Award winner played at a news conference last month.
Murray is a New York-based employee of Hendricks Sports Management, run by brothers Alan and Randy Hendricks. That agency also represented Knoblauch when he was playing.
In the Mitchell Report, released in December, McNamee said he injected Clemens at least 16 times with steroids and human growth hormone in 1998, 2000 and 2001.
Clemens has denied the allegations in several settings, including a news conference Jan. 7 in Texas. During that televised appearance, a 17-minute tape was played of what Clemens' representative said was a Jan. 4 conversation with McNamee recorded on the pitcher's side.
Two days after the Mitchell Report was released, Pettitte acknowledged McNamee injected him with HGH twice while the pitcher was recovering from an injury. McNamee said he acquired HGH from Radomski for Knoblauch in 2001.
Radomski pleaded guilty in April to federal felony charges of distributing steroids and laundering money. He is scheduled to be sentenced next Friday.