John Ryder beat Zach Parker to win the interim WBO super-middleweight title - and move closer to a bout with Mexican legend Saul 'Canelo' Alvarez.
After a thrilling opening four rounds in London, Parker pulled out of the fight at the start of the fifth round, citing an injury to his right hand.
It was Parker's first loss in 23 bouts.
Ryder could now fight Alvarez in May or be upgraded to full world champion if the four-weight world champion decides to not fight at this weight next time.
The fight, held at the O2 Arena, was tipped to be one of the best domestic fights of the year and it was living up to its billing before the anti-climatic ending as Parker walked to Ryder at the start of the fifth saying he could not continue.
It began at a frantic pace, with Parker the more mobile earlier on, but also sustaining some minor bruising under his right eye in the first.
The Derbyshire man had some success working to the Ryder body in the second, although the Londoner was unhappy with what he thought was a low blow before he landed some jabs at the end of the third - which Parker smiled at.
Ryder followed that by landing a beautiful left hook in the fourth, the best punch of the fight, and produced an attack straight after with the bell stopping Parker from getting in further trouble.
But that was to be the last of the action.
More to follow.
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