Back to the grind for world champion Xu

Pool ace hoping perseverance pays as he resumes glory bid for China

Starts, strokes and turns - for a lung-busting two and a half hours, Xu Jiayu repeats these drills with unwavering intensity and concentration. And all this following a two-hour gym session earlier in the day.

The unglamorous monotony of striving to be a world champion was painfully evident as the 24-year-old Xu pushed his limits at the Chinese national team's recent winter camp in Kunming, Yunnan province.