Switzerland's Fabian Cancellara powered his way to his second Olympic medal in four days, beating Sweden's Gustav Larsson to take the gold in the men's time trial.
American Levi Leipheimer finished more than a minute behind Cancellara for the bronze in the 47.3 km race against the clock that took just over an hour to complete.
Cancellara surprised himself with the bronze in the men's 245-km road race under sweltering conditions on Saturday but was the pre-race favourite for the time trial. As he crossed the finish line he pumped his arm in victory.
He then staggered off his bicycle and collapsed along some barriers while trainers poured water over him.
"One hour and 2 minutes is a really, really tough race," Cancellara said. "Now is the moment to enjoy and to be happy and proud that I won."
"I'm very, very happy and very proud of this ride today and to go home with two medals," added the 27-year-old two-time world champion in individual time trial.
In the first half of the race, the powerful Swiss time trial specialist kept switching leads with Spain's Alberto Contador. But Contador dropped off in the final lap and finished fourth.
Cancellara said he reached speeds up to about 80 kph (50 mph) on the downhill sections, but it was the long, tough uphill that taxed most of the riders.
In the women's event America's Kristin Armstrong was quickest, finishing ahead of Briton Emma Pooley.
For a long time, Pooley hung on in the gold medal position until she was taken down just one peg by the Armstrong who was 24.29 seconds quicker.
Karin Thurig of Switzerland, described by Pooley as her "hero", could only manage third, 34.98 seconds slower than the London-born Phd student.
Olympic champion Nicole Cooke was thrilled when Pooley — who had done so much to help her win gold — got a medal of her own today.
The Welshwoman described Pooley's contribution to her victory in Sunday's road race as "critical". As there are no team medals in cycling, the 25-year-old Phd student only had Cooke's gratitude for her efforts.
"She was a very critical part of my gold medal on Sunday and it's absolutely brilliant Emma's got her own medal today," said Cooke.