Colombian Carlos Tamara (left) delivers a left hook to the kisser of Filipino-American Brian Viloria (right) dethroning the latter as IBF light flyweight champion via a 12th round technical knockout Saturday. (Photo by BOB DUNGO JR.)

Filipino-American Brian Viloria collapsed shortly after losing his International Boxing Federation (IBF) light flyweight champion belt to Colombian Carlos “El Olimpico” Tamara via a 12th round technical knockout (TKO) Saturday at the Cuneta Astrodome in Pasay City.

A semi-conscious Viloria, whose record dropped to 26-3, with 15 knockouts, had to be taken to the Makati Medical Center where he had to undergo CT scan.

“He was responding to us when we talked to him on our way to the hospital though he was complaining of headache,” said Games and Amusements Board ring physician Dr. Redentor Viernes.

Referee Bruce McTavish stopped the fight at 1:45 into the 12th round when Tamara started to connect at will against the defenseless Viloria, who is known as “The Hawaiian Punch.”

After a tentative opening round, Viloria made his move and connected some counter rights in the next three rounds that bewildered Tamara.

Viloria, who was making his second defense of the crown he won in April of last year at the Araneta Coliseum, rocked Tamara with a left hook to the body under a minute left in the fourth round.

The 26-year-old Tamara, however, tried to fight back and connected a few wild shots while Viloria continued with his body attacks.

Viloria, 29, had a strong eighth round as he rocked Tamara with a left hook to the jaw. The Ilocos Sur-born Hawaiian, however, was starting to look worried as his Colombian opponent was getting more aggressive despite being bombarded with telling blows.

“That was our cue to apply our fight plan, when we sensed Viloria was starting to get tired. Though we were behind, we never lost hope because we knew Viloria will be strong the first half of the fight,” said chief trainer Butch Sanchez.

True enough, it was the opening the Colombian fighter needed to start his fightback.

In the 9th round, Tamara changed his strategy by first fighting southpaw then throwing a left uppercut that wobbled Viloria. The change in stance, which Sanchez said they perfected in training, turned out to be the biggest puzzle for Viloria in the fight. Viloria started to miss wildly the rest of the way that enabled Tamara to counter with punishing uppercuts to the head and body.

Viloria was already a spent fighter entering the 12th but tried to fight instinctively by throwing wild shots three times, missing all of them as well as his balance.

Tamara finally went for the kill as he connected a barrage of shots to a now defenseless Viloria, forcing referee Bruce McTavish to intervene and declare a halt of the bout at 1:45 of the 12th canto.

“I knew Viloria was starting to get weak by the 8th round. My corner kept on reminding me about my two children who wanted me to come home a world champion,” said Tamara in a post-fight interview.

Had Viloria finished the fight and went to the scorecards, he would have kept his belt as judges Somsak Sirianant of Thailand and Joe Garcia of Arizona had the Hawaiian fighter ahead, 105-104 and 106-103 respectively.

Judge Ray Reed of Australia had it 105-104 for Tamara.

Even if Tamara won the last round, Viloria would still keep his belt via a split draw.

In the main supporting bout, World Boxing Organization (WBO) minimumweight champion Donnie Nietes won a 10th round technical knockout over late replacement Jesus Silvestre of Mexico in their non-title tiff.

Silvestre survived a first round knockdown and fought toe-to-toe but faded in the later rounds. The Mexican spit his mouthpiece but refused to have it back despite the prodding of his corner.

Referee Ver Abainza then declared Nietes (26-1-3, 15 KOs) winner via TKO at 1:37 of the final round.