Isinbayeva urges rivals

The 25-year-old Russian, who claimed her second world title in Osaka on Tuesday, does not believe she will be able to better her current world record of 5.01, which was set two years ago, unless she is made to try harder.

"I need stronger competition in order the break the world record," Isinbayeva said. "My rivals need to do better."

Gold in Osaka capped a tremendous four-year spell for Isinbayeva, who has not been beaten in a major competition since the 2003 world championships, when her compatriot Svetlana Feofanova claimed gold.

She has broken the world record 20 times during the two years and was awarded the title of female athlete of the year in 2004 and 2005 by the IAAF.