Former National under-14 champion Aarthie gave India a deserving World crown after the defending girls' under-12 champion Koneru Humpy's challenge was subdued in the final rounds of the World Boys and Girls age-group chess championships.

Humpy, the 1998 World champion and top seed, finished second a consolation after the Andhra girl led her category midway through the championships.Aarthie defeated Wang Yu of China in the final round this morning to end a suspense filled day as the World crown depended on her outright victory.The Indian was unexpectedly beaten in the penultimate round last night by sixth seed Jana Jackova of the Czech Republic and was in danger of losing her sole lead to Evgenija.

The high drama continued as the Russian drew her 10th round game and both the aspirants went into the final roundwith eight points each.

Evgenija defeated second seed Dana Reizniece in four hours to jump into the lead with nine points to her credit. At this point, Aarthie was still fighting with the Chinese, but she had a clear goal win her game and overtake Evgenija on a better progressive score. In the girls under-12, Humpy drew her final round game with Munguntaul Batkhuyag of Mongolia and finished runner-up.

In the penultimate round last night, Humpy lost to second seed Sabrina Vega Gutierrez of Spain, but she maintained her second position.

Nana Dzagnidze of Georgia became the world champion in the under-12 category.In the under-16, P Harikrishna won his final two rounds to finish on a respectable score of eight points and is likely to finish either sixth of seventh.