Many of the marquee Olympic track and field events are over, but there are still some big races to be run before the Games conclude in London. Here are the most exciting races left on the slate in London.
Women's 4x100m Relay
The women's 4x100-meter relay figures to be an electrifying race. The qualifying heats were closely contested, as Ukraine edged out Jamaica for first in the heat by a hundredth of a second.
With most of the individual sprinting events out of the way, the relay offers some of track's biggest stars another chance to medal and make these Olympics memorable.
In the first heat, USA looked dominant, winning its heat with a time of 41.64—merely three-tenths of a second away from the world record of 41.37. With the final coming up, the Americans could have a shot at breaking the record.
Men's 4x100m Relay
After Jamaica swept the men's 100-meter individual race, it's hard to imagine the Jamaicans not coming out victorious in the relay version of the race.
This race probably won't be close, but what makes it a marquee event is the possibility for a world-record time. At the 2011 World Championships in Daegu, South Korea, the Jamaican team of Nesta Carter, Michael Frater, Yohan Blake and Usain Bolt set a new standard for greatness in the race with the world-record time of 37.04.
With the Olympic spotlight on the Jamaican team, can it break its own barrier?
Women's 4x400m Relay
The women's last chance to take center stage in track will be the women's 4x400-meter relay.
The USA sprinters and Jamaican sprinters have developed quite the rivalry during these Games, and the women's 4x400 will offer one last shot at a medal and bragging rights when both teams will make their runs at the gold.
Team USA edged out Jamaica in this race at the World Championships. The team of Sanya Richards-Ross, Allyson Felix, Jessica Beard and Francena McCorory posted a world-leading time of 3:18.09. Meanwhile, the Jamaicans posted a time of 3:18.71.
With just six-tenths of a second separating these two teams, there will certainly be fireworks when the two run for gold in the Olympic final.