Judges Salven Lagumbay and Edward Ligas had identical scores of 115-113 for Domingo, while Johnny Davis called it a 114-114 draw.
It was Domingo's fourth successful defense of the crown he seized by dethroning Joel Bauya of Emil Romano Stable via ninth round technical decision on July 30 last year at the San Andres Sports and Civic Center in Manila.
In a frightening undercard, the hard-hitting Bert Batawang of SGG Stable scored a one-punch knockout Rey Orais at 1:14 of the first round.
After being caught by Batawang's bone-cracking right, Orais fell prone on the canvass and it took him about 15 minutes to regain full consciousness, according to a report by philboxing.com.
Undefeated welterweight prospect Mark Jason Melligen of Cebu's famed ALA Boxing Gym also looked very impressive in stopping former RP champion Rex Marzan at 1:36 of round two for his fifth straight win in as many fights as a pro.
Not to be outdone, ALA Boy Rocky Fuentes flattened veteran Mindanao brawler Rolly Mandahinog at 43 seconds of the second round to bolster his chance to fight next for the vacant WBO Asia-Pacific flyweight crown.
Talisay's pride Rashied Bacus did not let his hometown fans down by pulling off a unanimous decision victory over Jerry Manganip of Butuan City.
The rest of the bouts saw Reman Salim of SGG Stable winning by technical decision at 36 seconds of round six over Rico Genon, Rogen Flores stopping Roel Honor at 2:45 of the first round, and Marjo Borres getting past Ranie Pamatian by unanimous verdict.