Arevalo opened up a three-stroke lead over Aaron Dimabuyo with the day’s best round.
Matet Salivio’s 75 pushed her one up on Katrina Gonzales in girls Class A, Magnum Bakunawa was just one stroke ahead of Mikee Camitoc after a 73 in boys Class B (13-14 years), Gerileen Handog (81) inched ahead of Mabel Salivio (82) in girls Class B.
Save for Bambee dela Paz who posted an 81 and ended the day with a one-stroke lead over Cyna Marie Rodriguez and Mia Piccio in girls Class C, Steven Limandibrata, Wolen Juan Superal, Dottie Ardina, Bino dela Paza and Ma. Christina Potenciano worked on comfortable margins going into the second round.
Limandibrata erected a six-stroke lead over Ernest Joseph Plata and Jordan Mamaril in boys Class C (11-12) with a 78, Superal (72) was up by seven over Michael Limandibrata in boys Class D (9-10), Ardina (73) pulled away from Katya dela Cruz (93), dela Paz (80) surprised JR Gonzales with a four-shot lead in boys Class E (8-under) and Potenciano (85) was far ahead of Princess Superal (112) in girls Class E.