Reigning silver medallist Y Prathiba shot into sole lead with a finely crafted victory over last round's joint leader and compatriot Kruttika Nadig in the fifth round of the girls' section in the Asian Junior chess championship in Negombo, Sri Lanka, on Tuesday.

The college girl from Chennai, with 4.5 points, is half a point ahead of Vietnam's Luong Phong Hanh and compatriots -- defending champion Tania Sachdev and Saheli Nath.

Top seed women's International Master Dronavalli Harika recovered from successive defeats in the last two rounds, scoring over local player Dayananda in a one-sided encounter.

Harika went down to Kruttika and Prathiba in the last two rounds and the defeats considerably lowered her chances for a comeback in this section.

In other top board games, Tania fought hard in a Sicilian Sveshnikov but her Vietnamese opponent Hanh held on to clinch half a point in 52 moves.

Earlier in the fourth round, played last evening, Tania had a smooth victory over Rajasurya while Nadig played it out  safe, settling for peace against Hanh.

Six more rounds remain in the championship, where the stakes are high as the winner will be awarded the International Master title along with a Grandmaster norm.

In the Open section, five boys -- International Master and defending champion Deepan Chakkravarthy, former World under-12 champion Deep Sengupta, Abhijit Gupta, Akshayraj Kore (all Indians) and Akbarnia Seyed Arash of Iran -- emerged joint leaders, tallying four points each from their first five games.

Half a point adrift of the leaders are top seed Nguyen Ngoc Truong Son of Vietnam, the Indian trio of P Magesh Chandran, G Rohit, S Poobesh Anand and Khamzim Olzhas of Kazhakhastan.

Playing in the top board, Kore chose the closed Sicilian and took a safer route leading to a draw with Arash. Going in for the queen for double rook ending, Kore settled for perpetuals when things looked like going out of hand.

Arash is proving to be a darkhorse in the section with a steady show and remains a thorn in the Indian camp.

It turned out to be a day of peace as the top three boards ended in draws.

Twelve-year-old Nguyen Ngoc Truong Son of Vietnam, the top seed with an Elo rating of 2435 points, played out a quiet draw with defending champion Deepan Chakkravarthy today.

"He is extremely good in endings, and is definite Grandmaster material," opined Deepan after conceding the draw.

In the fourth round, Kore was the big winner when he defeated higher rated IM norm holder G Rohit in a keenly-contested game.