Former world champion boxer Carl Frampton has issued legal proceedings against ex-manager Barry McGuigan.
The Belfast fighter lodged a writ at the High Court in Northern Ireland in connection with alleged earnings from some of his bouts.
The action has been taken against Barry McGuigan, his wife Sandra McGuigan and Cyclone Promotions (UK) Ltd.
It forms the basis of Mr Frampton's counter-claim to separate legal proceedings brought against him by Cyclone Promotions at the High Court in London.
A preliminary hearing in Belfast to decide the proper jurisdiction for the boxer's claim has been adjourned.
Mr Frampton, a former two-weight world champion nicknamed 'The Jackal', split with the McGuigan family-run Cyclone Promotions last summer.
In November it emerged that the 30-year-old Tigers Bay-born fighter is facing an action from his former promoters.
Those proceedings centre on an alleged breach of contract.
At the time Mr Frampton's lawyers pledged to defend the action and counter-claim on a number of grounds.
A lawsuit has now been brought by the boxer against Barry and Sanda McGuigan, as directors in the now dissolved Cyclone Promotions (UK) Ltd, and another company set up in the same name.
The writ refers to contracts for bouts in Northern Ireland, England and the United States.
But before any allegations are examined a decision is to be made on whether the case should be heard by a court in Belfast or London.
Arguments on that preliminary point are expected to be heard later this month.
Proceedings come as the boxer, who is now working with promoter Frank Warren, prepares for his next fight in April.
Mr Frampton is due back in the ring to take on Nonito Donaire at the SSE Arena in Belfast for his second bout since losing his WBA title to Leo Santa Cruz in January 2017.
A spokesman for Cyclone Promotions said: "The issues between the parties are subject to litigation and therefore it is not appropriate to comment at this time."