Olympic great Michael Phelps acknowledged "regrettable" behavior and "bad judgment" after a photo in a British newspaper yesterday showed him inhaling from a marijuana pipe.

In a statement to The Associated Press, the swimmer who won a record eight gold medals at the Beijing Games did not dispute the authenticity of the exclusive picture published Sunday by the tabloid News of the World.

"I engaged in behavior which was regrettable and demonstrated bad judgment," Phelps said in the statement released by one of his agents. "I'm 23 years old and despite the successes I've had in the pool, I acted in a youthful and inappropriate way, not in a manner people have come to expect from me. For this, I am sorry. I promise my fans and the public it will not happen again."

News of the World said the picture was taken during a November house party while Phelps was visiting the University of South Carolina.

While the newspaper did not specifically allege that Phelps was smoking pot, it did say the water pipe is generally used for that purpose.

The party occurred nearly three months after the Olympics while Phelps was taking a break from training, and his actions should have no impact on the eight golds he won at Beijing. He has never tested positive for banned substances. The case is unlikely to fall under any doping rules.

Phelps' main sanctions most likely will be financial — perhaps doled out by embarrassed sponsors who might be reconsidering their dealings with the swimmer.