Bong-blowing Olympian Michael Phelps did little to repair his image with the tech crowd on Tuesday as the 14-time gold medalist bowed out at the last minute as a keynote speaker at a major IBM conference.According to reports, Phelps called IBM general manager Al Zollar on Monday night to inform him that he was canceling his scheduled Tuesday keynote address at IBM's Pulse 2009 conference in Las Vegas. Unfazed, IBM quickly went to the bench and brought in former Los Angeles Lakers great Magic Johnson as a replacement.

"I was seriously bummed this morning when Al Zollar announced that Michael Phelps would not be speaking at the Pulse conference," wrote IBM social media strategist Tiffany Winman, in a blog post from the event. "Al explained that another exciting keynote speaker was on the agenda for later, but wouldn't tell us who it was. The Twitter crowd immediately started speculating who it would be -- Chris Rock?"

"A series of Pulse speakers proceeded to joke about the possibility of Al speaking in a Speedo as a Phelps replacement," noted Winman.

Ultimately, Johnson turned out to be a good draft pick for IBM, according to Winman. "Magic Johnson came off as a darling to the crowd. He was very intelligent and personable -- walking amongst the Pulse attendees, asking them to stand up, giving them long hugs, speaking and engaging with them directly, and encouraging personal photo opportunities," she wrote.

Phelps was embarrassed earlier this month when a picture of him smoking a bong -- a tube-like device used to inhale marijuana -- was published by a British newspaper. Since then, the athlete has been dumped as an endorser by cereal maker Kellogg's and was suspended from the U.S swim team.