PHILADELPHIA (AP) -- Olympic swimmer Brendan Hansen lost his gold medal from the Beijing Games during a flight in the United States and got it back a day later.

The American breaststroke specialist was returning to Austin, Texas on Sunday after visiting his suburban Philadelphia hometown for a bachelor party, said his mother, Miriam Hansen. He was carrying the medal he won for the 4x100-meter medley relay, the race that gave Michael Phelps his record eighth gold.

The medal fell out of a side pocket of Hansen's backpack, which he kept between his legs during the flight. He realized the medal was gone when he was getting off the plane, his mother told The Associated Press on Tuesday.

"I don't have my medal," the 27-year-old swimmer told his mother by phone. "It's not in my bag."

Hansen informed Southwest Airlines, Philadelphia police and USA Swimming. A woman who found the medal on the floor in the back of the plane saw that it was from the relay event and contacted police, Miriam Hansen said.

Police advised her to contact the University of Texas, Hansen's alma mater, on the belief that any swimming medalist in the area probably was affiliated with the school. The university called Hansen and asked, "Brendan, are you missing something shiny?"

Hansen finally met the woman who found the medal, gave her a check, and said she promised to donate the money to charity.

Miriam Hansen said she wants to know everything that happened, but that didn't interest her son.

"All he thought was, 'I have my medal back, what difference does it make?"' she said.

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