Koki Kameda won a unanimous decision over Alexander Munoz of Venezuela to claim the vacant WBA bantamweight title in a world championship doubleheader Sunday, making him the first Japanese boxer to win world titles in three weight divisions.

The eldest of the three Kameda boxing brothers won the decision after Daiki Kameda, the second eldest, retained his WBA flyweight belt with a split decision over 14th-ranked Romanian Silvio Olteanu.

Koki pounded the Venezuelan in the final round, narrowly missing a knockout after sending Munoz to the canvas once as his opponent was literally saved by the bell at Saitama Super Arena.

"I have no words. My father was against me fighting in this bout," said Koki. "He said, 'The bantamweight is too soon for you, Koki.' But today I got this result. I'd like to just say one thing to him. 'Pop, whadya think now!'," he said.

The belt became vacant when Anselmo Moreno of Panama was elevated to "super champion" status by the World Boxing Association two months ago. Neither Koki nor Munoz had any previous experience at bantamweight.

Koki captured his first world title in August 2006 with a split decision over Juan Landaeta of Venezuela in the WBA light flyweight class.

He claimed his second when he defeated then-WBC flyweight champion Daisuke Naito by unanimous decision in November 2009.

Meanwhile, Daiki fought well early but ran out of steam in the second half of the bout, while Olteanu continued to throw punches until the finish.

Two judges favored Daiki by scores of 116-112 and 115-113, with the other judge scoring 118-110 for Olteanu.