Devon Alexander will be forced to fight Kell Brook or relinquish his world title, Sportsmail can reveal.
The 25-year-old was due to face Brook on February 23 in Detroit but pulled out on Monday after injuring his biceps.
Floyd Mayweather Jnr then tweeted that he was close to agreeing a unification fight with Alexander for the IBF and WBC welterweight titles in Las Vegas on May 4.
But the IBF has confirmed that Alexander will not be allowed to sidestep Brook without giving up
his belt.
