The failure of Olympic gold medalist Ye Shiwen to finish among the medals at the women's 200m medley in the world championships is one of the big shocks of the first two days of racing in the pool.

The 17-year-old was off the pace throughout the race and made the final turn in last place, before her strong freestyle took her to fourth.

"I was expecting to do better," she said. "But after the first 100m I felt pretty bad in the water. I tried to catch up in the breaststroke (third leg), but it left me too much to do over the last 50m."