Norwegian hurdle star Karsten Warholm seems to be in good World Championship form. In Poland's Diamond League competition, the 29-year-old set a new world annual best with 46.28 when he won the 400 meter hurdles.
Warholm is the reigning world champion and also Olympic champion after the gold in Paris last year.
This year's World Championship in athletics will be held in Tokyo, starting on September 13.
