Oscar Pistorius advanced to the 400-meter final at the South African championships on Friday, attempting to become the first amputee athlete to run in the Olympics.

The double-amputee runner and Olympic hopeful smiled after the race, knowing he has a shot at winning South Africa's national 400-meter title on Saturday.

Pistorius cruised through the last 100, looking to his left and right and appeared content to finish fourth in 47.91 seconds. He earlier clocked 48.24 in windy conditions in the heats at the NMMU Stadium.

Pistorius needed to race here to be eligible for selection for the London Olympics.

Former world champion Caster Semenya will compete in the 800 final at the university stadium. The 21-year-old Semenya will run in her second two-lap race of the Olympic year under new coach Maria Mutola.

Last month, she ran 2:03.60. Semenya needs to run another 1:59.90 time to qualify for her first Olympics. Her time at the world championships last year in Daegu, South Korea, also counts toward Olympic qualifying.

She has at least two more meets in South Africa after the nationals and a number of European events to ensure she's eligible for selection.

Pistorius began his season with a run of 45.20 in Pretoria, giving him his first qualifying time of the season. That left him needing one more run of 45.30 or better in an international meet.

Is he thinking about London yet?

"I'm flirting a little bit with the idea," Pistorius told The Associated Press while trackside. "The team still has to get selected. My job is just to work hard until then and prove I'm in the right condition to be quite a strong 400 meter athlete if I get called up."

Athletics South Africa ruled that athletes who want to go to the London Games must appear at the South African championships, attracting Pistorius, Semenya, 2008 Olympic silver medal-winning long jumper Khotso Mokoena and former men's 800 world champion Mbulaeni Mulaudzi to the meet.

Mokoena, South Africa's only medallist at the Beijing Olympics, lost to Zarck Visser in the long jump final.   Mulaudzi made the 800 final, winning his heat in 1:49.28, but the 2009 world champion faces a tough road to reach London after an injury-hit season in 2011.

World championship bronze medal winner L.J. van Zyl advanced to the 400 hurdles final, finishing first in his heat in 52.23 seconds. Van Zyl's participation in Port Elizabeth fulfilled his requirements and qualified him for selection for London. He had already registered two Olympic qualifying times.