Enzo Maccarinelli suffered the seventh defeat of his career as he lost to WBA light-heavyweight champion Jurgen Brahmer in Rostock, Germany.
The Welshman's trainer, Gary Lockett, pulled his fighter out after the end of the fifth round with the 33-year-old's right eye completely closed.
A clash of heads in the first round caused the problem, with German Brahmer, 35, also suffering a cut eye.
But southpaw Brahmer increased the damage with his accurate left hand.
Former cruiserweight world champion Maccarinelli had hoped his height and reach advantage would prove the difference against Brahmer, who has lost just two of his 45 contests.
But while Maccarinelli was badly hampered by the damage inflicted to his right eye midway through the first round, Brahmer was hugely impressive as he took control from the second round onwards....