The International Olympics Committee (IOC) said critics concerned after 16-year-old Chinese Olympic swimmer Ye Shiwen took five seconds off her personal best and more than a second off the world record in the 400m individual medley should “get real”.
“These are the world’s best athletes competing at the very highest level,” IOC communications director Mark Adams said.
“We have seen all sorts of records broken already all over the place.”
His comments came after American coach John Leonard described Ye’s performance as “disturbing” and “unbelievable”.
But Mr Adams insisted London 2012 has “a very, very strong drug testing programme and we are very confident that, if there are cheats, we will catch them, as we already have done”.
Asked if he was disappointed that thoughts turned to doping whenever a world record was smashed, he added: “It is inevitably a sad result of the fact that there are people who dope and who cheat. But I equally think it’s very sad if we can’t applaud a great performance.”
British Olympic Association chairman Lord Moynihan also hit out at those who had raised suspicions about Ye, who has denied doping.