Nathan Cleverly has branded Juergen Braehmer "unprofessional" after the German pulled out of their WBO light-heavyweight title bout on Saturday.
Cleverly is already the 'interim' title holder and had been set to face the outright champion at the 02 Arena, but those plans fell apart on Wednesday morning when an apparent eye injury meant Braehmer failed to arrive in London ahead of the fight.
The Welshman's promoter, Frank Warren, is thought to be lobbying the WBO to strip Braehmer and upgrade his fighter to full champion status, or let him fight for the vacant belt this weekend.
Whatever the outcome of Warren's negotiations with the WBO, Cleverly has been left crestfallen.
The Cefn Forest fighter told Sky Sports News: "I'm absolutely devastated, to be honest. This is the fight that I really wanted.
"I've been gunning for Juergen Braehmer for over a year now - he's got the world title, he was the champion. I badly wanted to get this guy in the ring and win the title in style.
"It's very unprofessional that he hasn't turned up. He's ducked out of the fight as far as I'm concerned.
"The proof is there now that he doesn't want to fight me."
Braehmer's stock is already low due to the 32-year-old having only defended his belt once since winning it in 2009 while also pulling out of a January unification fight with Beibut Shumenov.
"I knew he didn't want the fight with me so I was a bit anxious, I knew he was a temperamental character and had a feeling he wouldn't turn up," Cleverly continued.
"I can't understand the mentality. He's taken the easy route and decided not to fight me, and it's so frustrating.
"He's let everyone down."
Cleverly has been preparing intensely for his defining night and training to face a southpaw, and said he would now have to refocus in the days ahead.
He said: "All my sparring has been against southpaws basically, so I'm going to have to mentally refocus now. I've got to make sure I'm on top of my game.
"As difficult as it is, I've just got to be professional about it."
The 24-year-old suffered similar frustration in December when Alejandro Lakatos pulled out of their fight for the interim title and he had to face late-notice replacement Nadjib Mohammedi instead.
A similar scenario is now set to play out this weekend, and Cleverly is adamant he will glean no pleasure from walking into the ring on Saturday - even if he has been elevated to full champion status in the meantime.
"As far as I know, maybe I'll be elevated to world champion, but as far as I'm concerned I'm still fighting on Saturday night against a ranked opponent for the world title, so my celebration will begin when I get the business done on Saturday night," Cleverly added.
Promoter Frank Warren was equally as scathing of the German champion and has vowed to do all he can to get him stripped of the title.
"Braehmer was meant to fly in at 1845 on Tuesday but cancelled and then again at midday on Wednesday but never got on the flight. They cancelled their hotel rooms on Wednesday morning but never told us," said Warren.
"They have not has the decency or the courtesy to contact us - we had to read about it on the internet. Something needs to be done and I'll be complaining to the WBO.
"It's not the first time this guy has done this and I want the WBO to strip him of the title. It just seems to me Braehmer never wanted this fight.
"But we will get an opponent for Nathan and I'm confident he will enter the ring as champion. Braehmer has not acted like a champion so therefore does not deserve to be one after this.
"He has a track record for it. He's a let-down. I couldn't give a s*** what happens to him after (he is stripped). He's nuts, the guy."
"But at the moment the people I feel most sorry for are Nathan and the fans who have bought tickets.
"Nathan has trained hard to fight a southpaw, trained the hardest he's ever done before but you can bet he won't be fighting a southpaw on Saturday when we get an opponent for him and that's a real problem.
"But we hope we will have a name before the close of business today. We are talking to a few fighters who have got good records and are ranked. It's just a matter of trying to agree terms with one of them."
One possible opponent could be Commonwealth champion Tony Bellew. The outspoken Liverpudlian has vociferously called for a showdown with the more experienced Welshman and is ranked in the WBO's top 20.