OMAHA, Neb. — Dara Torres has set an American record in the 50-meter freestyle at the U.S. Olympic trials, winning her semifinal heat in 24.38 seconds.

The 41-year-old beat the mark set in the previous heat Saturday night by Jessica Hardy, who touched first in 24.48. That knocked off the mark set in the morning preliminaries by Lara Jackson, who went 24.50.

Torres already is assured of being the oldest American ever to swim at the Olympics. She won the 100 free Friday night to complete her improbable comeback for a spot on her fifth Olympic team.