RIO DE JANEIRO (AP) — Brazilian sprinter Ana Claudia Lemos, the South American record-holder in the 100 and 200 meters, has tested positive for the anabolic steroid oxandrolone, the Brazil Anti-Doping Authority said on Thursday.

In a statement to The Associated Press, the authority only confirmed the case, and said Lemos requested the B sample be tested.

Brazil's athletics confederation said in another statement that it was still to be informed of the case.

The 27-year-old Lemos is Brazil's biggest hope for a medal in the 4x100-meter relay at the Rio de Janeiro Olympics.

Lemos' coach, Katsuhico Nakaya, could not be contacted by the AP.