Liam Smith will face Liam Williams in a rematch in Newcastle on 11 November, which will be an eliminator for the WBO light-middleweight title.
The fight has been pushed back from 28 October to avoid clashing with Anthony Joshua's title defence in Cardiff.
Smith, 28, won a controversial fight in April after Williams was withdrawn by his corner at the start of the 10th round because of a badly cut eye.
Williams felt the cut was as a result of a "blatant," headbutt by Smith.
The Welshman, 25, said the injury required plastic surgery.
Williams led on all three judges' scorecards at the time.
Victory for Smith extended his record to 25-1-1, while defeat was Williams' first in an 18-fight career.
Despite winning, Liverpool's Smith was not crowned WBO interim champion because of his failure to make the weight before the bout.
Puerto Rico's Miguel Cotto is the current WBO champion.
The title had been vacant since Saul 'Canelo' Alvarez relinquished the belt to move up to middleweight, and he will challenge Gennady Golovkin for the WBC, IBF, IBO and WBA Super world titles in September.
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