As Li Xiaoshuang of China celebrated his victory, six-time gold medalist Vitaly Scherbo looked around in bewilderment.
Li, the reigning world champion, scored a 9.787 on his final high bar routine Wednesday to win the all-around with 58.423 points, edging Russia's Alexei Nemov by just .049 points.
Scherbo, of Belarus, who won the all-around in 1992 and was chasing a record-tying seventh gold-medal, finished third.
The Americans turned in their best performance in the all-around since 1984, when Peter Vidmar won the gold. John Roethlisberger, who earlier said it would have been an understatement to even consider him a long shot for a medal, finished seventh.
Blaine Wilson finished 10th and John Macready was 29th out of 36 competitors.
It was only the second time since 1976 a gymnast from the former Soviet Union did not win the gold.
Li pumped his fists and hugged his coach after finishing his high bar routine. He ran off the podium grinning and waving to the crowd that was chanting his name.
It was a sweet victory for Li, who was bitterly disappointed by his performance in the team competition that gave China a silver medal. Li was bewildered by his errors _ including a shocking near-fall on the still rings _ and promised he would do better in the all-around.
He started the day in sixth place but moved up quickly. He was almost perfect in every routine and came into the sixth and final round trailing Nemov by just .038.
The two were competing at the same time, and Li appeared calm as he waited to begin. He stared down the high bar, oblivious to everything around him. He soared high above the bar, effortlessly flipping and twisting.
A grin began spreading over his face as soon as his feet touched the ground, and he began celebrating before the score was even announced.
Nemov, meanwhile, was solid on his floor routine until the very end. He knew he had lost the gold when he had to take a few short hops after his final tumbling pass, and he left the podium shaking his head.
Scherbo's scores were lower than he is used to getting, and his usual grin turned to a look of bewilderment with every score. After receiving a 9.687 for what looked like a solid vault, Scherbo slapped the floor. At other times he held out his arms as if to ask, "What more can I do?"