In his return to the spotlight for the first time since he retired, Mark McGwire volunteered to join the campaign against steroids and performance-enhancing drugs.
Yet McGwire's unwillingness Thursday to deny or confirm his own steroid use has already compromised his effectiveness as a spokesperson either slamming steroids or pitching products.
"His reputation is tarnished," said Gil Pagovich, a partner in Maxximum Marketing, a sports marketing firm. "No blue-chip company would ever think about using him in the near future."
During the congressional hearing McGwire refused to discuss the past while other accused sluggers, Rafael Palmeiro and Sammy Sosa, denied injecting steroids. Regardless of what they said, however, the vision of all three testifying may be enough to negatively affect their marketability.
Said David Carter, principal of the Sports Business Group: "Guys like Sosa and Palmeiro are great players, but the vivid imagery of being sworn in will resonate with decision makers for that Fortune 500 or consumer product company. That's not the kind of thing that they want in the head of a potential customer as they are pushing the grocery cart down the aisle."
McGwire's possible fall in the marketing world may not be significant, partly because he has led a quiet life since his retirement in 2001. He has neither a marketing agent nor a national endorsement deal following a campaign for Hardee's "Thickburger" last April. But his lack of endorsements should be no surprise; during the height of his popularity in 1998, his only deals were with McDonald's and one-time ventures with Walt Disney and MasterCard.
The price of McGwire collectibles is also expected to suffer. Because fake signatures are common and McGwire attended few autograph shows throughout his career, his signature was expensive when he signed a multi-year deal with Steiner Sports in 2003. The suggested retail price for a McGwire-autographed baseball was $899.
While some McGwire-signed items are still available, Steiner executives said nothing is going on discount after Thursday's hearings.
"He did well for us," said Larry Davis, Steiner's executive vice president, "though he definitely took a hit in the hearing. How could he not?"
Feelings about McGwire after Thursday's hearing seem to be mixed in St. Louis, where "Big Mac" finished his 16-year career and blasted into the record books with a then-record 70 home runs in 1998.
"I think people here in St. Louis are still willing to give Mark a pass," said Michael Barnes, the man who brokered deals to sell the most valuable balls from the McGwire-Sosa home run race of 1998. "There are auctions in this city all the time, and McGwire items still go through the roof."
Barnes said Barry Bonds, who was not called before the House Reform Committee, is in a more tenuous situation than McGwire.
"It's almost like Barry Bonds has a tougher road because he reportedly admitted to taking [steroids, though inadvertently], and he's still playing," Barnes said. "McGwire has built up a lot of goodwill [in St. Louis], whereas it seems like Bonds doesn't have much goodwill built up with anyone."
But others in St. Louis aren't confident that Thursday's congressional appearance didn't change the local view of McGwire.
"He was never much of an issue with the callers here," said Tony Hubert, executive producer of "590, The Fan," a St. Louis-based 24-hour sports radio station. "But yesterday, for every positive caller, there were five negative callers."
Darren Rovell is a senior writer for ESPN.com. He can be reached at firstname.lastname@example.org.