LOS ANGELES: Olympic swimmer Michael Phelps could yet find himself in hot water with sponsors after a British newspaper published a photograph that appeared to show him smoking marijuana, a sports business expert said Monday.

Initial reaction to the article was subdued, with at least two sponsors - Speedo and Omega - saying they had no plans to part ways with the 23-year-old Olympic hero who won an unprecedented eight gold medals in Beijing in August.

The News of the World published the photo on Sunday, allegedly showing Phelps inhaling from a glass pipe which is generally used to smoke the drug.