Yip, 16, is the Republic's best chance of winning its first Paralympics gold medal. She rewrote her own world record during this morning's heats. Her record time of 57.92 seconds was almost nine seconds ahead of Great Britain's Fran Williamson, who clocked one minute, 6.75 seconds for second-fastest qualifier.

The swimmer already has a silver medal and the world record from the 50m freestyle (S3) on Saturday.

Diagnosed with muscular dystrophy when she was a child, Yip's parents took her for swimming lessons to strengthen her muscles. She started training competitively two years ago.