Yuri Foreman faces six months on the sidelines following surgery on his right knee but his surgeons have predicted he will come back an improved fighter as he bids to become a world champion again.
Foreman, the 29-year-old Brooklyn-based student rabbi, had an operation to repair his torn anterior cruciate ligament and meniscus this week after his leg gave way before he lost his WBA light-middleweight title to Miguel Cotto on a ninth-round stoppage at New York's New Yankee Stadium.
Dr Laith M Jazrawi, who performed the 90-minute operation, said: "He's definitely going to be better now that his knee is stabilised."
Foreman, wearing a knee brace during his fights, had defied the long-standing injury, originally suffered when he was 15, to achieve his dream of becoming a world champion when he beat Daniel Santos last year.
But Dr Jazrawi said: "Any time that you have a deficient knee you can be predisposed to Yuri's type of injury."
Dr Gerald Varlotta, who diagnosed the injury two days after the defeat by Cotto and referred him to Dr Jazrawi said: "The fact that Yuri got to the level that he did on this previous ACL injury was a absolutely miraculous feat of perseverance and endurance.
"He's going to be stronger and have better push off of his right knee and perhaps more power and therefore better punching power and more stability.
"Yuri Foreman's boxing game has a lot to do with mobility and the only thing that he can do is become more mobile with a stable knee."
Foreman will begin a four-month rehabilitation programme next Monday and could be back in the ring in six months.