Jason Moloney has declared he will fight on as he grapples with the regrets of a failed world title defence and the prospect of starting from "square one in small hall shows".
The WBO bantamweight champion was dethroned by Japan's Yoshiki Takei in front of 55,000 at the Tokyo Dome on Monday night, an attendance record for an Australian boxer.
It was the 33-year-old's second defence of the title he won last year.
Moloney dominated early, before coming within "one clean punch" of an incredible final-round knockout win.
But he was unable to topple the staggering former kickboxing world champion, Takei left draped on the ropes as the bell sounded and judges rightfully awarded him a unanimous points victory.
"I can't stop thinking about it. I didn't sleep after the fight and played it over in my head a million times," Moloney told AAP from Tokyo on Wednesday.
The Australian spent the next day sightseeing with his partner, grappling with a missed opportunity that has denied him a big-money unification bout against any of the three other bantamweight belt-holders, who are all Japanese.
"I probably fought the wrong fight, took too long to make the adjustments," he said after watching some extended highlights on Wednesday.
"Tried to fight him a little too tactically.
"I did break him down eventually, but if I had put the pressure on a bit more I could have got there earlier.
"I was one clean punch away from an incredible victory.
"It's very easy in hindsight, but it's something that will always hurt me, the 'what could have been'."
Moloney will be re-ranked by all four recognised bodies and hopes his service to promoter Top Rank and popularity in Japan will help fast-track the next big shot.
"I'm not done yet,'' the Australian said.
"I've got it in me and hopefully the decent opportunities are there still and I'm not back to square one, fighting in the small hall shows.
"I'm trying to remain positive, but boxing's bloody brutal like that.
"It's such a big step back when you lose a world title.
"I've always been willing to fight anyone, anywhere, any time.
"(Top Japanese promoter) Mr Honda seemed to love my fight and really like me, and the Japanese people over here were insane.
"Even after the fight, I was out the front of the venue for an hour to get photos and autographs and everyone was saying 'please come back'."
The Kingscliff-based boxer will be in Perth to watch his twin brother Andrew fight for the WBC interim super flyweight belt on Sunday.
Moloney chose to fight in Japan instead of alongside George Kambosos Jnr in Perth on Sunday, a decision that was blasted as a mistake by former world champion-turned pundit Timothy Bradley in the early stages of Monday's fight.
"I haven't heard the commentary, but I've heard I don't really want to," Moloney said.
"Easy for Tim Bradley to say ... a guy able to fight his whole career in America and get paid millions.
"The opportunity was enormous and financially it made a lot more sense. No, I didn't sell out, but you take the best opportunities you can.
"It's something I'll never forget, looking into the crowd of people as far as I could see. It felt like a million people were there."