Usain Bolt looks to complete his second straight sprint triple crown Saturday on a hectic last night of athletics at the Olympic Stadium.

Bolt has already defended the 100 and 200 sprint titles he won in Beijing and now needs the help of his relay teammates to repeat in the 4x100, where Jamaica will be big favorites.

He is not the only athlete seeking a third gold.

Allyson Felix won her second - and with a world record - in the 4x100 meters on Friday after earlier winning the 200 and is running in the 4x400 on Saturday.

"This isn't the end for me," Felix said, looking forward to Saturday's relay. "It's just going to be exciting."

Medals will be awarded in 32 events Saturday, the penultimate day of the London Games.

The hopes of the host nation will again be pinned on long-distance dynamo Mo Farah, who hopes to add the 5,000 to the 10,000 title he won last Saturday.

In the women's 800, defending champion Pamela Jelimo of Kenya is favorite with world champion Mariya Savinova of Russia and 2009 champion Caster Semenya of South Africa also likely to be among the podium threats.

The men's javelin and women's high jump also will be decided on the final night at the stadium before it hosts Sunday's closing ceremony.

Also Saturday, Brazil aims to add an Olympic title to the country's five World Cup titles in the football final against Mexico at Wembley.

"We all know that we need to win the gold," coach Mano Menezes said. "Brazil has to win every tournament it plays, it needs to win every match it plays, even if it's a friendly. And this time even more because it's something the nation has never won before."

In other team finals, the heavily favored United States basketball team plays France, Norway takes on Montenegro in women's handball and it's the United States against Brazil in women's volleyball.

The Netherlands women's hockey team successfully defended its Olympic title on Friday by beating Argentina 2-0 at the Riverbank Arena and the country's men will attempt to make it a double Dutch hockey celebration when they take on defending champion Germany on Saturday night.

After riveting races on the road, velodrome track and BMX course, cycling moves out of London to Hadleigh Farm east of the capital for the women's cross-country mountain bike race.

China is in a strong position to win its seventh gold medal out of eight in diving in the 10-meter platform for men.

Qui Bo heads into the 10-meter platform semifinal on Saturday as the top qualifier with 563.70 points. His teammate, Lin Yue, was another 31.55 points behind in second. Final dives are Saturday night.

The men's modern pentathlon is run with competitors fencing, swimming, show jumping and then running and shooting in an event loosely based on the premise of a soldier attempting to survive behind enemy lines.

No less combative will be the final day of taekwondo at the ExCel arena.

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