About the only thing Poland's Pawel Nastula had trouble with was a sore neck. His judo opponents couldn't stop him.
The favored Nastula steamrollered his way through five foes to win the light-heavyweight event, beating South Korea's Kim Min-soo in the final.
Belgium's Ulla Werbrouck won the women's title in the light-heavyweight division, beating Japan's Yoko Tanabe.
Sandra Bacher of San Jose lost to Hannah Ertel of Germany in the first round and Rene Capo of Minneapolis, at 34 the oldest member of the American judo team, was beaten by Mevlud Lobjanidze of Georgia.
For the second time in two days, a competitor had trouble finding the weigh-in site. Jordan's Walid Al Awazem, as David Khakhaleichvili of the Republic of Georgia before him, could not locate the place to register.
Nastula opened quickly, beating 1993 world champion Antal Kovacs of Hungary with a stranglehold that forced submission.
Three times in his subsequent two bouts, Nastula had to stop to revive from a neck injury.
Eric Kreiger of Austria, injured Saturday in a bout against eventual gold medalist David Douillet of France, sustained a bruised spinal cord.
Estha Essombe of France was believed to have suffered a leg fracture in her bronze-medal bout with Italy's Ylenia Scapin.
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Medalists / Judo MEN'S LIGHT HEAVYWEIGHT
Gold: Pawel Nastula, Poland
Silver: Kim Min-soo, South Korea
Bronze: Stephane Traineau, France
Miguel Fernandes, Brazil
WOMEN'S LIGHT HEAVYWEIGHT
Gold: Ulla Werbrouck, Belgium
Silver: Yoko Tanabe, Japan
Bronze: Ylenia Scapin, Italy
Diadenis Luna, Cuba