Lewis Crocker has dropped trainer Billy Nelson as he prepares for the first defence of his IBF welterweight title in 2026.
The Northern Irishman edged a split-decision in his rematch with Paddy Donovan to take the crown back in September.
Since then, Crocker has pushed for a voluntary matchup before a mandatory challenger is established for the major strap.
Fans had expected that the star would continue to work with Nelson, but the latter has now revealed they have split ways.
"Lewis has changed coaches," he stated on X in reply to questions on Crocker's plans. "[He] has moved on to a coach in London.
"I no longer know what going on with him, but I hope he gets a voluntary defence in front of his fans in Belfast."
It marks the latest twist in Crocker's future, after a mandatory challenger bout between Donovan and Liam Paro was scrapped.
The former pulled out of the contest against the former light-welterweight champion citing illness, infuriating his opponent.
Matchroom boss Eddie Hearn, meanwhile, has suggested that Crocker could face Conah Walker in a rematch for his first defence.
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