The German kayaking great can quickly make up for that disappointment, though.
On Wednesday, Wagner-Augustin will be back on the water at Dorney Lake for the final of the 500-meter K-4, when she will look to top the podium at a fourth straight summer games.
"I want the gold in the K-4. I won't be satisfied with silver or bronze," said Germany's most decorated athlete at the London Games.
That's one of four gold-medal races on the first day of finals in the canoe sprint regatta, and Germany stands a good chance of winning all of them.
Although Adam van Koeverden of Canada qualified quickest for the blue-ribbon 1,000-meter K-1 final, Max Hoff of Germany has been the world's best over the distance since the Beijing Games in 2008, winning the last three European championships and world titles in 2010 and '11.
Sebastian Brendel won the 1,000-meter C-2 at this year's second World Cup event in Duisburg and the German continued that form by beating the reigning world and Olympic champion Attila Vajda in the semifinals here.
Hungary had the upper hand over longtime canoe/kayak rival Germany in qualifying times for the final of the 1,000-meter K-2 by nearly four seconds, and that should be a straight shootout for gold.
Wagner-Augustin has already won four golds at the last three Olympics but they have come in either the double or four. As an individual, though, she has come up slightly short.
She was fourth in Athens in 2004, won bronze in Beijing and didn't reach the eight-woman final in London after finishing fourth in her semifinal.
"I'm really disappointed," said the 34-year-old Wagner, who was seen being comforted by her husband after the race. "I wanted another medal in the single but it was only the second(-choice) competition for me."
The German four of Wagner-Augustin, Carolin Leonhardt, Franziska Weber and Tina Dietze were more than four seconds quicker than Hungary in the heats and have won the event at the last four Olympics, as well as both 2012 World Cup events and this year's European championship.
Hungary has won silver at the last three games.
Van Koeverden, the Olympic champion in the K-1 500 in 2004, apologized to his country after finishing in a surprise eighth place in the 1,000 in Beijing but he looked in prime form Monday to make up for that, easing through his heat and semifinals.
"I feel good, paddling well ... I hoped I wouldn't get blamed for unsportsmanlike behaviour, like someone who cruises over while looking around," he said.
Hoff, who is also in the final of the K-4 1,000, won the second semifinal a second slower than Van Koeverden. The defending champion is Tim Brabants of Britain, who squeezed into the final by less than five-hundredths of a second.
"The quality of the K-1 1,000 race is insane — the last four international races in the build-up this year has had a different winner," Brabants said. "Anyone could win."