British long jump hero Greg Rutherford said he's facing his "biggest challenge" since taking London Olympics gold Thursday when he goes up against his two predecessors at Shanghai's Diamond League meet. Rutherford, one of seven current Olympic champions in Shanghai, will face Beijing 2008 winner Irving Saladino and America's Dwight Phillips, the Athens 2004 gold-medallist who has been sidelined with injury for the last two years.

Kenya's world and Olympic 800m champion David Rudisha was one of 11 athletes to register season-best performances as the Diamond League opened in Doha on Friday. Rudisha won in 1min 43.87sec with Ethiopia's Mohammed Aman, the only man to have beaten the Kenyan in the last three years, taking second in 1:44.21. The Kenyan broke his own world record at the London Olympics last summer with a time of 1:40.91. "It's a season-best, but I can do better in the coming weeks," said Rudisha.

Kenya's world and Olympic 800m champion David Rudisha clocked the best time in the world this year with victory in Friday's Diamond League opener. Rudisha won in 1min 43.87sec with Ethiopia's Mohammed Aman taking second in 1:44.21. The Kenyan broke his own world record at the London Olympics last summer with a time of 1:40.91. asc/dj/as

Japanese teen sprint sensation Yoshihide Kiryu, the joint junior 100m world record holder, has revealed his target time for the season is 9.96 seconds after writing the figure on a school blackboard. The 17-year-old said he wrote goal on the athletics facility board at his high school after clocking the record equalling time of 10.01 seconds in a domestic race last Monday. "I've written it off the top of my head," Kiryu told reporters after finishing third in at the Seiko Golden Grand Prix, the third leg of the 15-round IAAF World Challenge series, in Tokyo on Sunday.