"Her (Saina) rivals are good players and very unpredictable, but Saina is mentally tougher than them. She also doing physically well. These factors should help her to do well in the World Championships," Kumar said.
Former chief national coach, Kumar said the World Championship will be an interesting and open battle because the Chinese girls, who were dominating the world stage, have not been successful for the last ten months.
"In the last one year - after the Asian Games - majority of the international games were won by four girls - Saina, Carolina Marin (Spain), Tai Tzu-ying (Chinese Taipei) and Ratchanok Intanon (Thailand) - these are the four girls that really dominated," he added.
Talking about the draw, Kumar said: "Saina has worked hard but it is a tough draw for her, because she is likely to face Japan's Takahashi in the prequarters and in the next stage, China's Wang Yihan.
"I don't want her to think too much on World Championship, but treat this tournament as super series ties. If she does this it will good for her. She is experienced and knows how to deal with it," Kumar said.
Replying to a query, Kumar said: "Earlier, there were only the Chinese who ruled the roost, but now it is between Carolina and Saina. For me whoever wins the world championship is world number one.