Bolt chases 'double treble'
London - Usain Bolt, the greatest sprinter of all time, will look to top off another epic Olympic campaign on Saturday when he goes in the 4x100m relay, chasing his third gold medal of the London Games.
The Jamaican, who already has the 100m and 200m golds under his belt, is eyeing a second consecutive Olympic golden treble after winning the 100m, 200m and 4x100m in Beijing.
Elsewhere on the final night of action in the Olympic Stadium, the decibel count will be off the charts as home favourite Mo Farah bids to add the 5 000m title to his 10 000m gold.
Bolt came to London with questions swirling over whether he was still the dominant force in world sprinting but he ran the second fastest time in history to win the 100m, and added the 200m title on Thursday.
But the Jamaicans will not have it all their own way, missing the injured Asafa Powell from their stellar line-up in a likely two-way battle with a powerful US team.
"It could be a world record but you can never say because it's a relay and it's a baton so you never know. But for me, we're just going to go out there and enjoy ourselves and run as fast as possible and it will be a good race to close the show again," said Bolt after winning the 200m.
Farah's first gold of these Games came in a glorious hour for Great Britain last week, after Jessica Ennis won the heptathlon and Greg Rutherford took a surprise long jump title.
The Somalian-born Farah, whose 10 000m victory was Britain's first ever over the distance, was caught up in some jostling in Wednesday's semi-finals as he battled fatigue, but he made it safely through.
"My body was a bit tired and I was not as fresh for the 5km as some of the other runners," he said. "I think it showed out there. It wasn't easy out there but I managed to qualify and I'm looking forward to the final."
He is likely to face stiff competition from American training partner Galen Rupp, who took silver in the 10 000m, and Bernard Lagat of the United States, who finished second behind Farah in the 5 000m at the 2011 world championships.
In the women's 800m final, South African star Caster Semenya will be looking to add the Olympic title to her controversial 2009 world crown.
The race will feature Semenya, defending champion Pamela Jelimo of Kenya and Russia's Mariya Savinova, looking to add Olympic gold to her world title from last year in Daegu.
Jelimo, just 18 when she won gold in Beijing, came to London looking to become the first woman to win the event twice at the Olympics.
Semenya had to undergo drug tests followed by gender tests following her magnificent victory in Berlin at the 2009 worlds, with the athlete complaining of "unwarranted and invasive scrutiny".
The South African was barred from the track for almost a year before being cleared to run again, and her comeback was hampered by a lower back injury.
The final day of athletics action on Sunday starts with the men's 50km race walk around the streets of London, with the women's 20km walk taking place in the evening.
Saturday's action in the stadium also includes the 4x400m women's relay, which the United States have had locked down since Atlanta in 1996, the men's javelin final and the women's high jump final.