Joe Calzaghe teamed up with Frank Warren in 1996
Joe Calzaghe's lawyers have filed a High Court counterclaim to Frank Warren's company Sports Network's legal case against the world champion boxer.
Calzaghe ended his 12-year association with Warren and Sports Network in June.
Sports Networks' High Court claim is Calzaghe broke a verbal contract with them to promote his further fights.
But Calzaghe's defence denies that and alleges Calzaghe is owed at least £2.43m ($4.55m) by Sports Network for his defeat of Bernard Hopkins in April.
Warren would not comment on the issue to BBC Sport, saying it was a "matter for the courts."
Just three days after Welshman Calzaghe announced his split with Sports Network, Warren's company filed a High Court action claiming the unbeaten boxer was in breach of contract which could cost Sports Network at least £1m.
But the defendant's summary of the High Court counterclaim reads: "There was no agreement (whether oral or in writing) made between the claimant and Mr Calzaghe on 15 January 2008 (or any other time) whereby the claimant was retained to act as promoter for Mr Calzaghe's fights after the Hopkins fight."
The 2007 BBC Sports Personality of the Year's proposed New York showdown with American legend Roy Jones Jr in November will probably be his last and Calzaghe is promoting it himself.
Warren with Ricky Hatton and Joe Calzaghe in 2002
But according to the legal papers submitted by both sides, Warren wanted to promote the 11-year champion's likely swansong.
In his legal defence and counterclaim filed on 7 August, Calzaghe alleges he had lost out financially and substantially to Warren since 2004 because Warren had acted as both Calzaghe's promoter and manager.
Calzaghe's document said the boxer had received only the minimum purse of £600,000 for each of his four fights agreed in October 2004 before his fight with Kabary Salem.
The last of that four-fight deal was Calzaghe's unification clash with Jeff Lacy at Manchester's MEN Arena in March 2006.
Calzaghe earned universal acclaim when he demolished American Lacy - dubbed the 'next Mike Tyson' - on points in one of the most one-sided contests for a generation.
But in his counterclaim, it states that shortly before his fight against Lacy he was told by Warren he would have to sign a written contract "which conferred on Mr Warren the right to promote Mr Calzaghe's next three fights."
Calzaghe fought Mikkel Kessler in November 2007 for the undisputed super-middleweight crown three fights after his destruction of Lacy.
And his defence states that two days before that Cardiff bout, "Mr Warren told Mr Calzaghe that he wanted him to sign a new promotion contract and a new management contract."
The counterclaim also alleges: "During that meeting and in order to persuade Mr Calzaghe to sign a new promotional and management contracts, Mr Warren told Mr Calzaghe that no broadcasting company other than Setanta was interested in the Kessler fight."
It claims Warren also told him: "Setanta had reluctantly agreed to broadcast the fight but only on condition that it also had the right to broadcast Mr Calzaghe's subsequent fight...
"The implication of this was that if Mr Calzaghe refused to sign new contracts, Setanta might refuse to broadcast the Kessler fight which, in turn, might result in the cancellation of that fight."
Calzaghe initially refused to sign new contracts before the Kessler clash at the Millennium Stadium but did put pen to paper the day before the weigh-in "in the belief that he had no realistic alternative."
So Warren's company promoted Calzaghe's American debut against the great Hopkins in Las Vegas but the court papers say the Newbridge boxer remained unhappy about Warren's company being his promoter.
The boxer's defence concludes Sports Network "has no contractual right" to promote the Roy Jones Jr fight which Calzaghe has arranged for 8 November.
No date has yet been set for the hearing.