Former world champion Caster Semenya will run her first 800-meter race of the Olympic year at a meet in northern South Africa on Saturday.
Semenya, who won silver defending her title at the world championships last year, will compete in the 800 at Potchefstroom. She's run just once competitively in 2012 — when she won a 400-meter race on March 3.
Semenya will run her first 800 with new coach and former Olympic champion Maria Mutola.
Mutola retired in 2008 with an Olympic gold medal and three world titles in the 800. She agreed to coach Semenya after the world championships in South Korea.
Athletics South Africa says men's 400-meter hurdler and 2011 world bronze medallist L.J. van Zyl will line up in the 400.
The pair are South Africa's best hopes for track medals at the London Games. It will be the first Olympics for the 21-year-old Semenya, if she makes the team.
Semenya has had a tumultuous three years since she won the 2009 world title in Berlin as a little-known teenager. She underwent gender tests and didn't compete for 11 months.
Semenya struggled last year with a persistent lower back injury and fell out with former coach Michael Seme just before the 2011 worlds, where she finished second to Mariya Savinova of Russia.
Sunette Viljoen, the South African who won bronze in the women's javelin at the worlds, also will compete on Saturday. Mbulaeni Mulaudzi, a former world champion and 2004 Olympic silver medallist, will run in the men's 800.
South Africa is targeting 12 medals at the London Games after only winning one silver, in the men's long jump, at the 2008 Beijing Olympics. That was the country's worst Olympic performance since its return at Barcelona in 1992 following the end of apartheid.