IBF light heavyweight champion Bernard Hopkins will have to wait a little longer to return to the ring for his title defense.

The 48-year-old Hopkins was set to fight No. 1 contender Karo Murat at the Barclays Center on July 13. Murat, though, was declared ineligible for the fight because he couldn't receive a visa by the United States Department of Homeland Security.

"This is an extremely disappointing development as we were anticipating Bernard making history once again on July 13 at Barclays Center," said Golden Boy Promotions CEO Richard Schaefer. "Since the administrative process that would have to be undertaken in order for Murat's visa petition to be reconsidered takes longer than six months, we're exploring several options with respect to Bernard's next fight."

The entire boxing card for July 13 was canceled.

When he does fight next, Hopkins (53-6-2, 32 KO) will become the oldest fighter in history to make his initial title defense. He defeated Travis Cloud at Barclays Center back in March to win the belt.

"I'm extremely disappointed about the fight being canceled," said Hopkins. "I was already in the gym, sparring and preparing for the fight, but things happen. I know Richard Schaefer and the staff at Golden Boy Promotions are already working on something bigger and better. I stay in shape so being ready is never a problem and I look forward to whatever fight is made for me in the near future."

Hopkins is the longest reigning middleweight champion in boxing history, and since reinventing himself as a light heavyweight following his 40th birthday, he has captured three world titles.

The 29-year-old Murat (25-1-1, 15 KO) has won several regional titles since becoming a pro in 2006. It's been nearly three years since his only loss, which occurred against Nathan Cleverly in 2010.

"Obviously I'm very disappointed as I have been in training for almost three months now, but I understand that my promoter's representative, Chris Meyer, is in talks with Richard Schaefer to discuss possible alternatives," said Murat.