Macau - Argentina's Cesar Cuenca moved a step closer to boxing history by beating China's "IK" Yang Lian Hui on points to win the International Boxing Federation (IBF) junior welterweight title in Macau on Saturday.

The undefeated Cuenca improved his professional record to 48 wins (2 KOs), just one short of Rocky Marciano's all-time 49-0 record as he won his first world title on his debut outside his home country.

He dominated from the start in a pulsating bout, knocking the unorthodox Yang (18-1, 13 KOs) backwards in the first round, which was controversially ruled a knockdown by inexperienced Filipino referee Danrex Tapdasan.

But from then on he largely outboxed the man from Dalian despite the Argentine being knocked down himself by a Yang right-hand in the fifth as the Chinese tried to chase down the elusive Cuenca.

A furious final-round flurry from brawler Yang proved too little too late, especially when the Chinese boxer was dubiously deducted a point by Tapdasan for intentionally throwing his polished opponent to the floor in a clinch in which it appeared both fighters were at fault.

The three judges awarded Cuenca the bout unanimously in his first ever appearance outside Argentina.

They scored it 117-108, 115-110 and 116-109 in Cuenca's favour, meaning the referee's interventions which cost Yang at least two points probably did not affect the outcome.

But veteran promoter Bob Arum was scathing in his condemnation of Tapdasan, stating afterwards: "That referee ruined the fight."

"It was one of the worst jobs of refereeing that I've ever seen," said the 83-year-old Arum, who has been in the fight game for more than half a century.

"It was just horrible. The first knockdown wasn't a knockdown. He was off balance and he didn't go down. He kept to his feet. It shouldn't have been called a knockdown.

"The point he deducted at the end was ludicrous. If it should have been deducted from anybody it should have been the other guy."

Cuenca's corner were vocal throughout the fight, complaining to officials at the end of every round about Yang's tactics and Arum felt the constant badgering had got to the inexperienced referee.

"He let himself be intimidated by the Argentine corner. I really have to question appointing somebody like that who has never refereed anything more than a six-round fight."

A delighted Cuenca revelled in his victory and said he would enjoy the moment before thinking about any boxing records.

"I think it was my experience that counted," a delighted Cuenca said.

"We worked so hard to prepare for this fight and he hurt me with some punches, but I was able to be a bit smarter than him."

Yang's trainer Justin Fortune was frustrated and said his man had not thrown enough combinations to score heavily enough against a nimble opponent with 13 years of professional experience.

"He was just throwing one shot at time, and it was never going to be enough," said Fortune.

Arum said his Top Rank organization would continue to promote the sport in Macau and China and keep up their quest to produce a Chinese professional world champion, despite the crushing double disappointment of seeing flyweight double Olympic champion Zou Shiming and now Yang lose world title fights already this year in Macau.

"With Yang we'll go back to the drawing board," said Arum. "I think he's very talented and he'll work his way back up."