Blood and urine samples of unified world super-bantamweight champion Marlon Tapales were taken by agents of the Voluntary Anti-Doping Agency on Thursday in Baguio City.

The visit came about a month before Tapales battles fellow two-belt champion Naoya "Monster" Inoue on 26 December in Tokyo.

Tapales will put his World Boxing Association and International Boxing Federation straps while Inoue will risk his World Boxing Council and World Boxing Organization jewels in a scheduled 12-rounder at the Ariake Arena.

The samples taken from Tapales during the unannounced visit are going to be brought to a World Anti-Doping Association laboratory for testing.

"The Voluntary Anti-Doping Association is an organization that will offer and promote effective anti-doping practices and programs in boxing and mixed martial arts," according to its website.

"Boxing and mixed martial arts are state regulated. Currently, few athletic commissions perform drug testing for performance enhancing substances. When conducted, testing is not comprehensive, rarely unannounced and not a deterrent. Sports regulators do not have the man-power, time and funds to thoroughly carry out the task. VADA will be an opportunity for athletes to demonstrate their commitment to clean sport."

Unbeaten with a 25-0 win-loss record, Inoue is the massive betting favorite to become undisputed champion at 122 lbs.

Holding a 37-3 slate with 19 knockouts, Tapales has been labeled as an easy prey, a tag the Filipino southpaw's camp feels is undeserving.

A former world champion at bantamweight, a victory over Inoue will make Tapales the first Filipino undisputed champion, an accolade not even Manny Pacquiao was able to become.

Tapales and his team will fly to Japan on 19 December where other members of his entourage from the United States and the Philippines will converge for one of the year's marquee matchups.