The draw, which came after 15 moves of a Pelikan variation of the Sicilian defense, increased Antonio’s output to seven points.
A half point behind him is fellow GM Eugene Torre who was held to a draw by two-time junior champion NM John Paul Gomez in 32 moves of a Slav defense.
Tied for second position with Torre with 6.5 points apiece are defending champion NM Emmanuel Senador and NM Ronald Llavanes who hurdled their respective opponents.
Senador defeated upset-conscious Ferdinand Leysa after 18 moves of a Sicilian Alapin while Llavanes subdued NM Yves Rañola.
The final round of the competition is being held as of presstime.
Close behind the leaders with six points and still in contention for the P50,000 top prize are IM Chito Garma who won over NM Nicomedes Alisangco, FIDE Master Jesse Noel Sales beating newcomer Fami Fazon, NM Rolando Andador, who beat Julius Sinangote and NM Rolly Martinez, who won over fellow NM Mirabeau Maga and Gomez.