The United States set the early pace in the women's gymnastics team event this afternoon but their top name, world all-around champion Jordyn Wieber, failed to make the individual final in a shock result.
Wieber, one of the biggest medal favourites coming into the Games, finished behind team mates Ally Raisman and Gabby Douglas in the all-around standings.
She now has no hope of getting one of the nation's two places in Thursday's fight for the individual title.
Wieber, 17, paid the price for a series of wobbles on the bar and a slight overstep on the floor as Raisman and Douglas, with whom she won the world team title last year, nailed slicker routines.
16-year-old Douglas, who beat Wieber in the US trials, had a big overstep on the floor herself, incurring a 0.3-point penalty, but did well enough on the other apparatus for the mistake not to matter.
"Today (Jordyn) wasn't quite as sharp," US team co-ordinator Marta Karolyi told reporters. " Ally's success today just proves that hard work pays off."
Wieber might not even make any of the four apparatus finals, depending on rival teams' scores later on Sunday.
"It was always going to be close between the three of us doing all-round and in the end it is what it is" - Marta Karolyi
"It was hard because of course I wanted that spot but I also wanted Ally to do her best for the team."
The US dominated the third of Sunday's five qualifying sessions to make sure of reaching Tuesday's team final.
The top eight teams, the best eight on each apparatus and the leading 24 individuals in the standings at the end of Sunday get to compete for medals.
Britain's Beth Tweddle ensured she should have a chance to add an Olympic gold to her two world titles on the asymmetric bars with a stunning routine, and a mark of 16.333, on the apparatus.
Tweddle, 27, had been unhappy with her floor mark of 14.433, but was all smiles after the bars, her final event.
"I am really pleased with the routine, I couldn't have asked for any more than that," said Tweddle, who had surgery on her knee three months ago.
A big crowd of uniformed soldiers, sitting in prime seats that had been left empty on the opening day, cheered on the British team.
"We got a standing ovation as we walked back along. It was amazing," said Tweddle. "It was so bizarre to suddenly see half a crowd of soldiers but it was really nice for them."
Uzbekistan's only representative in the gymnastics, Luiza Galiulina, who had been due to compete today, was provisionally banned from the Games after testing positive for a diuretic.