Jenz Tecson also faltered with an 82, but like Tanpinco, he remained in contention for the Class A crown together with Thailands Panuwant Muenlek.
"Considering the conditions out there, not to mention one mistake I made before the round, 77 was good enough," said Tanpinco, the defending champion from Bacolod City.
Tanpinco earlier forgot his golf shoes when he left the Dasmariñas Village house of Justin Limjap, where he was staying. But tournament director Gerard Cantada came to his rescue and bought a pair of shoes as his pair for his hole-in-one feat Tuesday.
Together with his first round 75, Tanpinco, 20, and a La Salle Bacolod sophomore, will start todays third round with a five-shot lead at 152.
Thailands Sanawong Tepphatud limped home with 82 to go with a first-day 75 as he slid to second with a 157, followed by compatriot Wutti Amrtarachotilmul a 164 after an 87.
Muenlek made an 81 to go with an earlier 80 to tie Tecson at 161 in the annual event organized by Philippine Junior Golf Federation headed by Boy Cantada and hosted by Wack Wack headed by its president Ben Abalos.
The Philippines Kevn Lachica came up with 83 to remain in contention in the division for players who are 15-18 years old.
Ninety-two players from eight countries are competing in the four-day event sponsored by Cebu Pacific, Herma Group of Companies, Milo and Philippine Amusement and Gaming Corporation.
Other backers are Airlift Asia, All Seasons Manpower Intl Services Inc., Bingo Bonanza, CRC Concrete Mix Corporation, Duty Free Philippines Fiesta Mall, Eaglecor Inc., EDSA Shangri-La Hotel, Foren Corporation, Gilberto Duavit, Junior Golf Parents, Wack Wack.
Magsaysay Maritime Corporation, Makati Foundry Inc., Mitsubishi Motors, Morelia Tours, Outback Steakhouse, Philippine Flour Mills, Pioneer Insurance, Takanobu Taira, Toyota Otis, Sysu International, Gourmets Cafe, Sen. Blas Ople, Rep. Willie Villarama and Triplex Tents.
The race for the team event is turning out to be tight as the Philippines, Thailand and South Korea are all tied at 165. Playing for the RP team are Kevin Lachica and Tecson.
Choo Tze Huang of Singapore scored an 82 to retain the Class B lead with 162. Second was compatriot Koh Deng Shan with 84-166, followed by Thailands Pomnnubpun Khainpukdee with 84-169.
Gian Carlo de la Paz was the best Filipino player in the division limited to players who are 13-14 years old. He shot 86 to be in sixth place with 179.
Thilands Anujit Hirunratanakom made an 82 to pace Class C, compatriot Namsub Padungsriseth shot a 69 to lead Class D and Chataya Chanachai, another Thai, carded an 85 to take the early girls Special Division lead.