JOHANNESBURG (AFP) - Sex tests were carried out on 800m champion runner Caster Semenya before her Berlin gold medal win, said South Africa's former athletics coach on Monday after he quit over the gender storm.

Wilfred Daniels, who announced his resignation at the weekend, said the International Association of Athletics Federations (IAAF) had noticed the teenager's phenomenal performance at the junior championships in Mauritius.

"Before Caster left for Berlin, she was then asked to go to a clinic here in Pretoria to undergo some of these tests but the tests were not explained to her properly," Daniels told private radio station Talk Radio 702.

"The normal urine or blood test - that is what she was told. According to the source that I spoke to, it was actually some sort of gender verification test that was done on her."

Athletics South Africa -- which has denied tests were done on the athlete since the storm broke -- told the radio station on Monday that proof of the allegations should be brought forward.

The 18-year-old powered to a 1min 55.45sec win -- the world's best this year -- in the 800m in Berlin last month shortly after the IAAF announced a sex probe.

Daniels said Athletics South Africa (ASA) and the IAAf had collectively "messed up" the situation which sparked outrage in South Africa and has seen the country rally behind the teenager who is from a rural village.

"Caster was put in this unenviable position where she had to endure what she had to endure because we didn't brief her properly, we didn't explain to her and we weren't proactive in anticipating what she might be confronted with when she came to Berlin," he said.

Daniels said he resigned over the "repulsive handling" of the matter, The Star reported.

"We did not handle Caster properly. The handling of the issue was atrocious."