Paul Williams has chosen Sergio Martinez to replace the injured Kelly Pavlik for his next fight, to be held in Atlantic City on December 5.
Williams, who holds the WBO welterweight title, had spent the autumn preparing to step up to face Pavlik, who was to have defended his WBO and WBC middleweight belts.
However, Pavlik had to back out twice because of an infection in his left hand and the bout was finally cancelled last month.
Williams (37-1, 27 KOs) is notably tall for a welterweight and can fight in several divisions. He has not been in the ring since a one-sided victory against Ronald 'Winky' Wright in April.
Argentina's Martinez (44-1-2, 24 KOs), meanwhile, is the WBC super welterweight champion but will move up to 160 pounds to face Williams.
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