Caster Semenya's coach has resigned because she was duped into believing she was undergoing standard doping tests instead of gender tests, according to newspaper reports on Monday.

"I'm so sorry for the part I played; because of my negligence she went through all that. I am so sorry we let you down," said Wilfred Daniels, who had been a coach with Athletics SA (ASA) since 1993.

"I had to leave. I just looked at myself and asked if I liked what I saw. I asked if I could really enjoy my life knowing what I know... My conscience was too great."

Daniels resigned from his job last week, saying ASA did not advise Semenya properly on the gender tests, neither did it brief her on what was happening when the story broke.

"I am not happy. I'm not pointing fingers at anybody because I am part of the collective responsibility and blame.

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

The International Association of Athletics Federations announced that gender tests would be done on Semenya after she won the 800 metres gold medal at the World Athletics Championships in Berlin last month.

ASA president Leonard Chuene declined to comment on Daniels' resignation.

"He has resigned - like anyone else resigning as far as I am concerned. If he has a story, then he must tell it," said Chuene.