The 14-year-old Mariano lost his way in their Sicilian-Najdorf game and resigned after 50 moves, ending a string of victories that gained him a crack at the championship. The setback dropped the Filipino bet from fourth to seventh place with 5.5 points in the 14-under division of the three-category tournament.
GN Gopal of India seized the solo lead with 7 points by beating Homayoon Toufighi of Iran. Five players shared second place with six points apiece, including Nijat Aghayev of Azerbaijan, top seed German Falko Bindrich, Ishaq Ahmed of UAE, Rostam Behmardi of Iran and Toufighi.
Mariano closes out his campaign here against Wais Ahmed, another 12-year-old bet from Syria, hoping to score a victory and boost his bid for a runner-up finish in the premier division.