China’s Ye Shiwen poses with her gold medal after winning the 200m individual medley at the London 2012 Olympic Games. Photograph: Toby Melville/Reuters

Ye Shiwen calmly takes another gold as drug claim storm rages around her

Chinese teenager at centre of doping allegations leaves the controversy – and her opponents – behind her in the pool

As eight swimmers took to the blocks for the women’s 200m individual medley at the Aquatic Centre on Tuesday night, it was impossible to distinguish, from their demeanour at least, which of them was at the centre of an international storm commanding the attention of the sport’s highest authorities.

All eight waved to the crowd, walked to their blocks, adjusted their caps, goggles and costumes, flapped their arms and jumped. The entry ofHannah Miley, the British record holder, in lane 1 was greeted with an enormous roar by the devoted crowd. But it was the white cap in lane 4 on whom all non-partisan eyes were focused.

Two minutes, seven seconds and 57 hundredths later it was all over, and the Chinese swimmer Ye Shiwen, after a thrilling final 50m that saw her take the lead from Australia’s Alicia Coutts, was a double Olympic champion.

The world of swimming may have spent 36 hours in a ferocious debate over the means by which she could achieve such astonishing feats, but the 16-year-old had other things on her mind. As the electronic beep sounded to mark the start of the race, she leapt from the blocks, put her head down, and swam.

Her victory was not a foregone conclusion. The teenager was not first off the blocks, and turned only in fourth place after the first butterfly length. She pulled back some of the ground in the middle 100m to turn second for home, but it was on the final freestyle leg that the race was won, when she inched ahead of the Australian, and finally took the race comfortably. Her time earned her a new Olympic record.