London: Allyson Felix won her second Olympic gold medal of the games and added a world record on top as she powered the US sprint relay team past its Jamaican rivals in the 4x100 meters.
The 200-meter champion ran a blistering second leg and 100 silver medalist Camelita Jeter finished off the world record job, pointing to the time clock with her mouth wide open as soon as she got past the line, seeing that the 27-year-old mark of the former East Germany was gone.
The USA team finished in 40.82 seconds, shaving a massive 0.55 seconds off the old mark. It was the second world record in as many days on the super-fast track of the Olympic Stadium after David Rudisha of Kenya set a mark in the 800 on Thursday.
No one came close to a world record in the 5,000, but Meseret Defar reclaimed the title she first won eight years ago, as her Ethiopian compatriot Tirunesh Dibaba missed a chance to become the first woman to repeat as double Olympic long-distance champion.
Defar swept past the front-running Dibaba in the final straight and had enough power to hold off Vivian Cheruiyot of Kenya. Dibaba, running with a huge blue tape on her inside right thigh, faded toward the end and was unable to produce the kick that gave gold in the 10,000 last week.
Once she crossed the line, Defar produced a religious image of a virgin and child to show to the cameras before breaking down, sobbing into the picture.
After she won at the 2004 Athens Games, Defar has often had to spend time running in shadow of Dibaba. Now the two combined to dominate their fierce rivals from Kenya over the long distance in London.
Ethiopia had already won the women's marathon in the center of the city last Sunday, and the favored Cheruiyot failed to even get close to her world championship double from last year.
Dibaba was one race away from achieving the long-distance equivalent of what Usain Bolt did over the sprints on Thursday.
Bolt's double in the 100 and 200 turned him into a self-proclaimed "living legend," and he rested on Friday while his 4x100 relay teammates toiled.
The Jamaican relay team still easily qualified for Saturday's final in 37.39 seconds, the fourth-fastest time in history at that stage. Then the U.S. team trumped them with 37.38 seconds for a U.S. record.
On Saturday, Bolt will have chance to show if he can make enough of a difference on the fast track to produce another world record.
The way Jamaican sprinters have been dominating over this year — with five of six medals in the 100 and 200 meters — it seems more a matter of passing the baton correctly than stretching for maximum speed.
With dual silver medalist Yohan Blake possibly handing off to Bolt for the anchor leg, it all seems set for a fitting finale to the Bolt show at the Olympics.