A fight involving Carl Frampton's mandatory WBA super-bantamweight challenger Guillermo Rigondeaux has been cancelled because of visa issues.
Jazza Dickens' fight against Rigondeaux in Liverpool on Saturday is off.
Frank Warren's Queensberry Promotions said Rigondeaux, who has been training in Russia, will "not be arriving in the UK" before the fight.
WBA and IBF champion Carl Frampton has been ordered to fight Rigondeaux after beating Scott Quigg in February.
Queensberry Promotions say 35-year-old Rigondeaux is currently in Miami "for some unexplained reason" having been due to fight the Briton on Saturday night.
"We are all extremely disappointed by the situation."
Rigondeaux applied for his UK visa in Moscow on 29 February, with Warren's company being told it would take five working days for the process to be completed.
It said it was told by the application centre that the visa would be issued by Wednesday at the latest and Rigondeaux "would then arrive in the UK shortly thereafter".
Queensberry Promotions claims that Rigondeaux boarded a flight to Miami on Tuesday.
It added: "We have yet to establish how and why he flew to the USA and, further, how he managed to fly anywhere when the normal practice is, when applying for a visa, that you hand your passport in and get it back when the visa is issued."
WBA bosses said former champion Rigondeaux - a two-time Olympic champion who is unbeaten in 16 professional bouts - must face Frampton before 27 July.