WASHINGTON (AP) — Kelly Blair was expecting to speak before a grand jury Tuesday investigating Roger Clemens. With his appearance postponed a week, the former bodybuilder and gym owner said again in an interview he never supplied Clemens with performance-enhancing substances.

Blair told The Associated Press he has taken steroids himself in the past and given them to other people, but “there were no pro athletes involved.” He said he has never met Clemens and denies providing the seven-time Cy Young Award winner with steroids or human growth hormone.

“They don’t have anything on Roger Clemens if they’re calling me up there,” Blair said by telephone from Texas. “If you are messing with me, you don’t have anything on this man.”

The federal grand jury has been meeting since January, trying to determine whether Clemens lied to Congress last year when he denied under oath the use of steroids and HGH. Blair said the scheduled date for his testimony has been changed three times, but he’s “pretty sure” that he’ll appear on Aug. 11. He said he plans to testify without a lawyer, although he has been consulting one for advice.

“Why do I need an attorney to go tell the truth?” he said.

Blair said he used steroids as a bodybuilder and helped provide them to other people until 2003. He has admitted that he once provided Andy Pettitte’s father, Tom, with human growth hormone. Tom Pettitte has said he has taken HGH to treat health problems.

Andy Pettitte also has acknowledged taking HGH. He told congressional investigators that former teammate Clemens acknowledged doing the same nearly a decade ago. That chain of names is all but certain to come up during Blair’s testimony, regardless of whether he had direct contact with Clemens.

“Do I personally think he took something?” Blair said. “Unless he’s wearing a Superman cape under his uniform. That’s something amazing he’s achieved at his age. But I don’t know him, so I can’t say.”

Blair called his own association with steroids a “mistake” and he has used them in the last six years only to help speed his recovery following a couple of operations.

“I learned my lesson about it,” Blair said. “I wish I’d learned my lesson when I was 20.”

Blair said the attention he’s received in connection with the Clemens case has ruined his business. He’s closed his gym but continues to work as a personal trainer.

“It’s just taken everything away from me,” he said. “I think I’ll have to file for bankruptcy. It’s just that bad – for something I didn’t do.”