LONDON — Maybe someone slipped graphite into their chalk bowl. How else to explain how China’s world champion male gymnasts ended up a sliphanded sixth in Saturday’s qualifying round. Or maybe the Americans loaded up with super glue. “Can we just get the medals now?” cracked Jonathan Horton after his teammates topped the table with a score of 275.342, nearly three points ahead of the Russians, who once never bothered watching them.

Unfortunately for the Yanks, the qualifying scores won’t count toward Monday’s championship round. But China, which flipped off the planet in its home gym four years ago, suddenly looks vulnerable after finishing second in its group to Great Britain, which hadn’t qualified a team until these Games. “We’ve had a long journey to get here,” proclaimed homeboy Louis Smith. “It’s monstrous.”

The Americans, who won bronze in 2008 and missed a silver at last year’s world meet in Tokyo by a 100th of a point behind the Japanese, now can legitimately dream of winning their first gold medal at a non-boycotted Games since 1904, when they were the only folks who showed up in St. Louis. Not that the US males were perfect. Horton, the only Beijing veteran, came off both pommel horse and parallel bars and Sam Mikulak slipped off the high bar.

But those were venial sins compared with the Chinese, who had two men fall off the horse and Guo Weiyang botch a tumbling pass on floor and his dismount from p-bars. The Japanese, who were second to China in Beijing and figured to benefit from any Sino slippage, watched in shock as Kohei Uchimura, their three-time world champion and odds-on favorite to win the all-around, messed up two events and doomed his colleagues to fifth place behind the Germans. “We will have to try not to make the mistakes that we did today,” mused Kazuhito Tanaka.

Monday, when the medals are handed out, the slate will be wiped clean. But for a day at Olympus, Uncle Sam’s nephews are on top of the world.