WBA and IBF super-middleweight champion Carl Froch has postponed plans to fight Julio Cesar Chavez Jr in Las Vegas in March after suffering an elbow injury in training.
Froch, 37, is targeting one final fight in the boxing capital of the world before a possible retirement and has been deep in talks with Chavez's camp.
But injury has derailed those plans, although Froch hopes to return to the ring in the summer.
"I'm disappointed to have to let this opportunity go but at this stage in my career, I have to make every fight count," said Froch, whose last fight was a stunning victory over George Groves at Wembley in May 2014.
"I will get some treatment and then we will look to make this fight or another big fight in the early summer."
Promoter Eddie Hearn said: "We have been deep in negotiations for some time and we were almost ready to go. Carl has gone into fights before not 100% fit and paid the price and he has made the right decision to hang fire. We will have a meeting early next week and plan out 2015. I'm confident we will see him back in the ring this summer."
Froch sparked rumours of a possible retirement on Sunday 18 January with a cryptic message on Twitter.