Audley Harrison has admitted that it will be difficult to continue his professional career following the 41-year-old's latest loss.
The former Olympic champion was beaten in the first round by American Deontay Wilder, who unloaded a series of punishing blows before the referee stepped in.
Harrison told BoxNation: "It was terrible on my part. I was focused in training, felt great, comfortable and calm, but then I got banged out.
"It's going to be hard to come back from here, no doubt about it. I've got to be realistic, I'm 41.
"It's going to be hard to get opportunities like this on the big stage again. It's looking like it could be the end."
Harrison now holds a 31-7 professional record.