Devon Alexander will make the next defence of his IBF welterweight title against undefeated American Shawn Porter on November 30.
The fight, which takes place in San Antonio, Texas, leaves Britain's Amir Khan without a date for his mooted pre-Christmas return.
Khan and Alexander had been in protracted talks for a clash that was thought close to being finalised for either New York or Dubai.
But with Khan holding out for a fight with Floyd Mayweather in May, Alexander needed to find an opponent for his voluntary defence which is now less then seven weeks away.
Porter enjoyed a stellar amateur career and has compiled a 22-0 record in the paid ranks with a draw against Khan's latest foe Julio Diaz, whom he beat decisively in a rematch only last month.
Alexander must face mandatory challenger Kell Brook following his fight with Porter, should he overcome the 25-year-old prospect.
However, Alexander, too, is hoping to secure a date with Mayweather next year and Brook would have to wait his turn if that unification fight is given the all-clear.