Tiu toppled 1,856 pins in eight games to lead the charge among 36 entries under squad I.
Tiu had an average of 232 points followed by Luther Tapaya of BTA with 223, after toppling 1,831 pins while James Zuluaga is at third spot with 1,824 pinfalls.
Germaine Uang is the highest placed bowler so far at fourth spot with 1,738 pinfalls and Wilbert Yu at fifth spot with 1,721 pins.
On the other hand, squad II which is for out of town bowlers were scheduled to play their first eight games last night with Benshir Layoso, the defending champion from Manila Tenpin Bowling Association (MTBA) is here to defend his title.
Aside from Layoso, Tyrone Ongpauco of Tenpin Bowling Association of Makati (TBAM) and a mainstay of RP team is also joining the event.
After their 16-game elimination round, the top 32 will advance to the finals tomorrow afternoon.