Daniel Dawson's hopes of securing a second crack at the WBO light-middleweight title were snuffed out in three rounds in Macau on Saturday night.
The 36-year-old Perth fighter was looking to put himself in the frame for another world title tilt by defeating highly-rated American Glen Tapia.
But Tapia, 25, was too good as he became only the second fighter to halt Dawson in 46 fights.
Dawson possibly shaded a quiet first round, certainly he indicated as much with a clenched fist to the crowd after the bell.
But Freddie Roach-trained Tapia (now 23-1) caught Dawson in the second, then a round later he stunned the West Australian before trapping him in the corner and landing a series of unanswered shots which forced referee Mark Nelson to end the contest after 1:42 of the third.
"I felt great starting the fight and unluckily got caught with a big shot that had me out on my feet," Dawson (40-5-1) said.
"I'm very unsatisfied with the result and at the same time very proud of myself, my team and my supporters as we took on one of the best and most dangerous young up and coming fighters in my division."
Dawson's manager Mike Altamura summed up the NABO title fight best: "Glen Tapia was just too good tonight."
The main event at the Cotai Arena saw Thailand's Amnat Ruenroeng retain his IBF flyweight title with a unanimous points victory over China's Zou Shiming.
The undefeated Thai was content to box at distance for much of the fight and, despite being knocked down in the second round, coasted home 116-111 on all three judges' scorecards as Zou struggled to land many clean punches.
It was a crushing defeat on home soil for China's double Olympic gold medallist and national icon Zou, who was fighting for the world title in just his seventh professional contest and only his second over the full distance of 12 rounds.
"It is part of life," Zou told reporters afterwards. "Without losing you cannot fully enjoy the sweet taste of victory.
"I don't think I was outboxed, just that he had more experience in this type of fight."
After a cagey opening, the fight briefly burst into life in the second round when Amnat went down after the first real flurry of punches that been thrown by Zou.
It looked liked the Thai had slipped over but the referee gave him a standing count.
Both boxers struggled to land clean shots in the opening half of the fight as they seemed content only to box from distance and grab and hold on once in close.
But it was Amnat, who improved his unbeaten record to 15 wins, who was able to prevent Zou from landing any flurries, dart away out of trouble with lightning speed and counter with occasional stinging ripostes of his own.
Despite having Manny Pacquiao's fabled trainer Roach in his corner, Zou appeared to lack the guile and craft to cut off the ring and trap the Thai, and never really threatened to hurt his opponent.
"We have to get back in the gym, work harder, come back next time and win," said Roach, who is due to fly back to Los Angeles on Sunday to supervise Pacquiao's preparations for his megafight with Floyd Mayweather on May 2.
"He was a very awkward fighter," Roach said of Amnat. "He ran a lot and countered. We didn't see him fight that way before on the tapes so we weren't prepared for it."
China has only once before had a world champion outside of the amateur ring, and that was at the little recognised World Boxing Council "minimum weight" (light flyweight) category which Xiong Zhaozhong won in 2012 and defended twice.
Zou, 33, won gold medals at the Beijing Olympics in 2008 and in London in 2012 to add to a bronze in the 2004 Athens games, as well as three amateur world titles (2005, 2007, 2011).
But instead, Hong Kong's Rex Tso could be China's next world champion after edging Michael Enriquez of the Philippines on points in a brutal World Boxing Association super flyweight title eliminator on the undercard of the Zou-Amnat bout.
"The Wonder Kid" from Hong Kong went toe-to-toe over 10 titanic rounds and burst into tears when awarded a unanimous points decision 95-94, 95-94, 96-93 on the judges' cards.
"I want people when they think of Hong Kong in the future to think of Rex Tso, not just Bruce Lee," an emotional Tso, 27, said at ringside after improving his unbeaten record to 16 wins.
The victory secured the first ever world title shot for a boxer from Hong Kong, pitting Tso against Kohei Kono, the WBA super flyweight champion from Japan, at the same Macau venue on July 18.
The eccentric undefeated Yang Ik (19 wins, 13 KOs), from Dalian in northeast China, also shone for China by putting himself in line for a shot at the IBF light welterweight title.
The 29-year-old constantly switched stance, showboated and ultimately battered the experienced Patomsuk Pathompothong (31-2-2) of Thailand into submission, stopping his 31-year-old opponent midway through the sixth round of their final eliminator.
The exuberant Yang celebrated by draping himself in the Chinese flag and shouting "I always put on a show!", during what proved an evening of mixed emotions for the predominantly Chinese crowd in the Cotai Arena.
"I am not really happy with tonight," he told AFP afterwards. "Because my big brother Zou should have been making history for China."